--- type: Quiz title: "Unit 1 Physics Quiz: 202 MCQs for OSSC, CGL, RRB & Govt Exams" canonical: "https://www.easy2crack.com/mcqs/physics/unit-1-physics-quiz-uAqXUnuh" subject: physics questions: 202 free: true updated: null tags: ["mcq", "practice", "physics"] --- # Unit 1 Physics Quiz: 202 MCQs for OSSC, CGL, RRB & Govt Exams 202 multiple-choice questions with answers. ## Q1. An air bubble in water behaves as a: A. Concave Lens B. Concave Mirror C. Convex Lens D. Plane Mirror **Answer:** a ## Q2. While magnets attract many magnetic substances like iron, they can also repel: A. Diamagnetic substances B. Ferromagnetic substances C. Non-magnetic substances D. Paramagnetic substances **Answer:** a ## Q3. Rocket works on the principle of: A. Newton's First Law B. Newton's Second Law C. Newton's Third Law D. Pascal's Law **Answer:** c ## Q4. A fuse is a: A. Safety device and regulates flow of current B. It is made up of Tin and Lead alloy C. Has low melting point D. All of the above **Answer:** d ## Q5. Which law states that"when any gas is expanded or compressed st constant pressure, its volume is didectly propertional to its absolute temperature"? A. Boyle's Law B. Charle's Law C. Dalton's Law D. Gay Lussac's Law **Answer:** b ## Q6. Which of the following electrical device senses the temperature of a physical system and performs actions so that the system's temperature is maintained near a desires setpoint? A. Compressor B. Relay C. Thermograph D. Thermostat **Answer:** d ## Q7. Which of the following statements as regards Gravitational Force is NOT correct? A. It is a short range force B. It is conservative in nature C. It is the force of attraction between two masses D. It is the weakest force in nature **Answer:** a ## Q8. Which of the following is a Scalar quantity? A. Force B. Energy C. Momentum D. Torque **Answer:** b ## Q9. What happens when a 100 watt bulb and a 60 watt bulb are connected in a series? A. Both the bulbs will glow equally B. Only the 60 watt bulb will glow but not the 100 watt bulb C. The 100 watt bulb will glow more than the 60 watt bulb D. The 60 watt bulb will glow more than the 100 watt bulb **Answer:** d ## Q10. "The phenomenon in which electrically charged particles are released from or within a meterial when it absorbs electromagnetic radiation" is known as: A. Doppler Effect B. Modulation Effect C. Photoelectric Effect D. Tyndall Effect **Answer:** c ## Q11. When number of turns in a coil is tripled, without any change in the length of coil, its self inductance becomes: A. One-third B. Three times C. Six times D. Nine times **Answer:** b ## Q12. Which of the following properties of sound is affected by change in air temperature? A. Amplitude B. Frequency C. Wavelength D. Intensity **Answer:** c ## Q13. Who was the first scientist to enunciate the Quantum theory? A. Albert Einstein B. Louis de Broglie C. Max Planck D. Niels Bhore **Answer:** c ## Q14. Which electronic device stores electrical energy in an electric field? A. Capacitor B. Diode C. Resistor D. Transister **Answer:** a ## Q15. The wave length of which of the following types of electromagnetic waves is the shortest? A. Gamma rays B. Infrared rays C. X-rays D. UV rays **Answer:** a ## Q16. Which of the following is applicable in case of the hydraulic brakes used in the automobiles? A. Archimedes principle B. Bernoulli's principle C. Pascal's Law D. Torricellian law **Answer:** c ## Q17. Which one of the following pairs of the process of heat transfer and corresponding medium is incorrectly matched? A. Absorption-A polished surface B. Conduction-A solid surface C. Convection-A fluid surface D. Radiation-A vacuum **Answer:** a ## Q18. Which of the following is responsible for the formation of the phenomenon of 'Mirage'? A. Angle of incidence of light is larger than the critical angle B. Angle of incidence of light is smaller than the critical angle C. Decreased absorption of light by air at higher temperature D. Increased absorption of light by air at higher temperature **Answer:** a ## Q19. Image formed by a plane mirror is: A. Real at the surface of mirror and enlarged B. Real, behind the mirror and of same size C. Virtual, behind the mirror and of the same size D. Virtual, behind the mirror and of the enlarged size as the object **Answer:** c ## Q20. The blue colour of water in the sea is due to the : A. Reflection of blue sky by sea water B. Reflection of blue light by impurities in sea water C. Scattering of blue light by water molecules D. Absorption of other colours except blue by water molecules **Answer:** c ## Q21. Potassium graphite and Calcium graphite can be mostly used as: A. Lubricants B. Moderators C. Semi-conductors D. Superconductors **Answer:** d ## Q22. Which among the following does provide colours to fine-cut diamond? A. Existence of definite plamar layers B. Presence of impurities C. Variance in refractive index D. Variance in transparency of diamond **Answer:** b ## Q23. On which of the following scientific principles is an electric generator based? A. Faraday's Law of electromagnetic induction B. Law of thermodynamics C. Newton's Law of Motion D. Superconductivity **Answer:** a ## Q24. Knot' is the unit of : A. Acceleration B. Depth C. Distance D. Speed **Answer:** d ## Q25. The work done to move a unit charge from a point to another is called: A. Conductance B. Current C. Potential Difference D. Resistance **Answer:** c ## Q26. Which among the following is a non-conservative force? A. Electrostatic force B. Frictional force C. Magnetic force D. Spring force **Answer:** b ## Q27. The inability of a body to change its state of rest or uniform motion by itself is known as: A. Displacement B. Force C. Inertia D. Momentum **Answer:** c ## Q28. In which of the following cases the apparent weight of a body in an elevator becomes zero? A. During free fall of a body under gravity B. When the elevator is accelerating downwards C. When the elevator is accelerating upwards D. When the elevator is at rest **Answer:** a ## Q29. When a body is immersed in a liquid the upward force experienced by it is known as: A. Centrifugal force B. Hydraulic force C. Tangential force D. Buoyant force **Answer:** d ## Q30. Which of the following is responsible for the production of an echo? A. Absorption of sound waves B. Reflection of sound waves C. Refraction of sound waves D. Transmission of sound waves **Answer:** b ## Q31. The purity of Milk is measured by the instrument known as: A. Barometer B. Lactometer C. Hydrometer D. Hypsometer **Answer:** b ## Q32. The equipment SONAR is used to determine the: A. Depth of the Seabed B. Intensity of an earthquake C. Cruising altitude of an aircraft D. Speed of a moving object **Answer:** a ## Q33. Who invented Dynamo? A. Michael Faraday B. Gutenberg C. Macmillan D. Pascal **Answer:** a ## Q34. Name the physicist who is credited with the discovery of the Neutron. This 1932 discovery led to his winning the Nobel Prize. A. Enrico Fermi B. J.S. Fleming C. James Chadwick D. Max Plank **Answer:** c ## Q35. Which law of Physics states that "The force between the two electric charges reduces to a quarter of its former value when the distance between them is doubled"? A. Coulomb's Law B. Stefan's Law C. Pascal's Law D. Hooke's Law **Answer:** a ## Q36. 1 horsepower = approximately__________ watts. A. 746 B. 764 C. 647 D. 1024 **Answer:** a ## Q37. ________ expansion makes the Effel Tower taller during summers. A. Gradient B. Thermal C. Gravitational D. Physical **Answer:** b ## Q38. What is the name of the phenomena in Physics and astronomy which involves the splitting of a spectral line into two or more components of slightly different frequency when the light source is placed in a magnetic field? A. Lumen Effect B. Alpenglow Effect C. Zeeman Effect D. Raman Effect **Answer:** c ## Q39. Which of these is the energy conversion that happens in the process called photosynthesis? A. Potential energy to Chemical energy B. Light energy to Chemical energy C. Heat energy to Chemical energy D. Heat energy to Light energy **Answer:** b ## Q40. What is the colour of the light emitted by the Sun? A. White B. Red C. Yellow D. Orange **Answer:** a ## Q41. Name the law in Physics which states that" Equal volume of all gases under the same conditions of temperature and pressure contain equal number of molecules". A. Avogadro's Law B. Boyles's Law C. Ohm's Law D. Charles's Law **Answer:** a ## Q42. The total number of images formed by two mirrors inclined at 120 degree to each other is___________. A. 4 B. 3 C. 2 D. 1 **Answer:** c ## Q43. Which of the following is used as a substitute of Mercury in thermometers? A. Arsenic B. Galinstan C. Selenium D. Bromine **Answer:** b ## Q44. Who among the following scientists invented the Cotton Gin? A. Sonny Perdue B. Norman Borlaugh C. Eli Whitney D. George Washington Carver **Answer:** c ## Q45. Ozone at the higher level of the atmosphere is a product of _________ acting on oxygen molecules. A. X-rays B. UV radiation C. IR radiation D. Gamma rays **Answer:** b ## Q46. The power of a lens is -2.0 D. Here 'D' stands for: A. Dilation B. Distance C. Dioptre D. Degree **Answer:** c ## Q47. Which among the following has its refractive index closest to that of crown glass? A. Sapphire B. Ruby C. Diamond D. Canada Balsam **Answer:** d ## Q48. The rating for a fuse used in a household electric circuit is provided on the basis of: A. Resistance B. Current C. Power D. Voltage **Answer:** b ## Q49. Why do water droplets always take a round shape when dropped onto plane surfaces? A. Due to atmosphereric pressure B. Due to exersion of surface tension by the molecules C. Due to gravity D. Due to the presence of Eddy Currents in the air **Answer:** b ## Q50. The audible range of sound for human beings is from: A. 10 Hz to 100 kHz B. 20 Hz to 20 kHz C. 10 Hz to 10 kHz D. 20 Hz to 200 kHz **Answer:** b ## Q51. The sky appears blue due to: A. Refraction of light B. Reflection of light C. Scattering of light D. Dispersion of light **Answer:** c ## Q52. The Tyndal Effect is due to: A. Dispersion of Light B. Reflection of Light C. Refraction of Light D. Scattering of Light **Answer:** d ## Q53. _______ is one of the most important technique for the separation of a mixture by passing it in solution or suspension through a medium in which the components move at different rates. A. Filtration B. Evaporation C. Chromatography D. Distillation **Answer:** c ## Q54. The power of lens is measured in________. A. Candela B. Kelvin C. Ampere D. Diopter **Answer:** d ## Q55. Which of the fololowing is a Vector quantity? A. Electric field B. Electric current C. Electric charge D. Electric flux **Answer:** a ## Q56. The inertia of an object is measured by its_______. A. Area B. Volume C. Mass D. Speed **Answer:** c ## Q57. Heat, in ______, is a type of energy transfer from a warmer substance to a cloder one. A. Friction B. Gravity C. Thermodynamics D. Magnet **Answer:** c ## Q58. Which of the following quantities is measured using a Torsion Balance? A. Pressure B. Force C. Charge D. Magnetism **Answer:** b ## Q59. Who among the following introduced the concept of electric field for the first time? A. Michael Faraday B. Charles Augustin de Coulomb C. Joseph Henry D. Maxwell **Answer:** a ## Q60. Archimedes : Buoyancy : : Newton : ______ A. Gravity B. Motion C. Force D. Pressure **Answer:** b ## Q61. Through which one among the following materials does sound travel slowest? A. Air B. Glass C. Water D. Steel **Answer:** a ## Q62. Optical fibres are mainly used for which of the following ? A. Communication B. Weaving C. Musical instruments D. Food industry **Answer:** a ## Q63. Radar is used for : A. Receiving signals in a radio receiver B. Studying the movement of planets C. Detecting and fixing positions of objects e.g aeroplane D. Studying the Sun spots **Answer:** c ## Q64. Which of the following instruments is used to measure the depth of the oceans? A. Altimeter B. Fathometer C. Hydrometer D. Manometer **Answer:** b ## Q65. One Fermi is equal to: A. 10-6m B. 10-8m C. 10-10m D. 10-15m **Answer:** d ## Q66. Why do the rain bearing clouds have a dark colour? A. They absorb all sunlight falling on them B. The condensed water droplets are saturated with dust particles C. They scatter all sunlight falling on them D. They reflect all sunlight falling on them **Answer:** c ## Q67. We notice a spark while pulling out the electrical plug of an appliance. Which of the following properties of the appliance is responsible for this? A. Capacitance B. Conductance C. Inductance D. Resistance **Answer:** a ## Q68. What is the function of heavy water in a nuclear reactor? A. It is used as coolant in the nuclear reactor B. It enhances the speed of the neutrons C. It slows down the speed of neutrons D. It heat up the ractor **Answer:** a ## Q69. Wahich of the folowing is NOT true for the cathode rays? A. They are positively charged B. They cause mechanical motion C. They produce heating effect D. They travel in straight line **Answer:** a ## Q70. Which of the following process is used to prepare industrial Hydrogen? A. Bayer process B. Bessemer process C. Bosch process D. Haber process **Answer:** c ## Q71. A passenger falls in the forward direction when a moving bus applies brakes to stop and falls backwards when it accelerates from rest. This is because of________. A. Force B. Displacement C. Inertia D. Momentum **Answer:** c ## Q72. Which one of the following has only magnitude and no direction? A. Velocity B. Force C. Work D. Momentum **Answer:** c ## Q73. Find the odd one out. A. Retardation B. Deceleration C. Negative acceleration D. Positive acceleration **Answer:** d ## Q74. The line that joins the centre of curvature and the pole of a curved surface is called: A. Focus B. Principle axis C. Focal point D. Radius of curvature **Answer:** b ## Q75. It is the product of power and time; its unit is W-s and KWH. What is it called? A. Power B. Potential Energy C. Electric Conductance D. Electrical Energy **Answer:** d ## Q76. _______ is the change in velocity per unit time. A. Acceleration B. Momentum C. Force D. Inertia **Answer:** a ## Q77. When the angle between the force and displacement is 90 degree, the work done is_______. A. Neutral B. Negative C. Zero(no work is done) D. Positive **Answer:** c ## Q78. Which of the following examples illustrates Newtown's first law of motion? A. When we stop pedaling, the bicycle begins to slow down B. When a bus starts suddenly, the passengers receive a backward jerk C. Launching of a rocket D. While catching a fast moving cricket ball, the fielder gradually pulls his hand backwards with the moving ball **Answer:** b ## Q79. 746 Watts is known as: A. 1 Pascal B. 1 KW C. 1 Joule D. 1 Horse Power **Answer:** d ## Q80. _______ is a quantity that does NOT describe the nature of a wave. A. Wavelenth B. Altitude C. Wave speed D. Frequency **Answer:** b ## Q81. In the formula F = GMm/d2, what is G called? A. Greater height B. Gravitational Force C. Acceleration due to gravity D. Universal Gravitational constant **Answer:** d ## Q82. Linear momentum is equal to : A. Mass * Velocity B. Speed * Weight C. Force * Height D. Mass * Volume **Answer:** a ## Q83. Work can only be done when there is _______. A. Momentum B. Energy C. Power D. Force **Answer:** b ## Q84. In longitudinal waves, the particles vibrate in a ________ direction of propagation. A. Planar B. Perpendicular C. Parallel D. Semicircular **Answer:** c ## Q85. Sound is prouced due to _______. A. Refraction B. Vibration C. Rotation D. Reflection **Answer:** b ## Q86. _______ determines the speed of sound in a medium. A. Tone of the wave B. Timbre of the wave C. Properties of the medium D. Amplitude of the wave **Answer:** c ## Q87. Work done on an object do NOT depends on: A. Displacement B. Angle between force and displacement C. Force applied D. Mass of the object **Answer:** d ## Q88. Which of the following equations represents the Velocity-Time relation? A. s = ut + 1/2 at2 B. 2as = v2 - u2 C. v = u + at D. v = u - at **Answer:** c ## Q89. 1 Coulomb/1s = ________ A. 1 watt B. 1 volt C. 1 ampere D. 1 ohm **Answer:** c ## Q90. Which of the following forces is NOT electromagnetic in nature? A. Force of Friction B. Weight of body C. Electrical force in spring D. Tension in a string **Answer:** b ## Q91. What is the value of the Gas Constant 'R'? A. 8.31 J/K.mol B. 8.35 J/K.mol C. 8.32 J/K.mol D. 8.33 J/K.mol **Answer:** a ## Q92. Which one of these is an example of conversion of electrical energy into mechanical energy? A. Iron box B. Television C. Electric fan D. Torch **Answer:** c ## Q93. Where does the centre of gravity os any freely suspended object lie? A. Directly beneath the point of suspension B. Immediately below the centre of the object C. At the centre of the object D. On the ground **Answer:** a ## Q94. Abody rolling down on a hill has: A. Kinetic energy only B. Potential energy only C. Only frictional force D. Both kinetic energy and potential energy **Answer:** d ## Q95. ______ is the rate of doing work. A. Velocity B. Energy C. Power D. Force **Answer:** c ## Q96. Sound waves with frequencies below the audible range are called: A. Supersonic B. Infrasonic C. Ultrasound D. Ultrasonic **Answer:** b ## Q97. A ray of light passes from water to glass. It bends: A. Towards the normal and speeds up B. Towards the normal and slows down C. Away from the normal and speeds up D. Away from the normal and slows down **Answer:** b ## Q98. The point where entire weight of an object acts is known as the _______. A. Centre of gravity B. Centre of friction C. Centre of mass D. Centre of pressure **Answer:** a ## Q99. The gravitational force of attraction between a satellite and the Earth gives rise to ______. A. Centripetal force B. Tension C. Centrifugal force D. Planar force **Answer:** a ## Q100. ______ is the commercial unit of energy. A. Joule B. Watt hour C. Kilowatt hour D. Kilowatt **Answer:** c ## Q101. Clouds looking white in colour are due to the phenomenon of ________. A. Reflection of light B. Scattering of light C. Refraction of light D. Radiation **Answer:** b ## Q102. In which of the following activities is work said to be done? A. Pinki is walking on a leveled road with a box on her head B. Rahul is pushing a wall of a house but fails to do so C. Shruti is sitting on a chair D. Harsh is reading a book **Answer:** a ## Q103. An object is released from a certain height above the ground. Just at the time it touches the ground, it will possesses________. A. Kinetic energy B. Heat energy C. Potential energy D. Chemical energy **Answer:** a ## Q104. ______ is preventing by coating the conducting wire with pvc. A. Fusing B. Overloading C. Short-circuit D. Dripping **Answer:** c ## Q105. To change a temperature from the Kelvin scale to the Celsius scale, you have to : A. Divide the given temperature by 273 B. Substract 273 from the given temperature C. Multiply the given temperature by 273 D. Add 273 to the given temperature **Answer:** b ## Q106. During the fall of an object, which of the following energies increases at any point in its path? A. Chemical energy B. Mechanical energy C. Kinetic energy D. Potential energy **Answer:** c ## Q107. The kinetic energy of the particles is maximum in the case of______. A. Solids B. Plasma C. Liquids D. Gases **Answer:** b ## Q108. An object is placed in the front of a concave mirror at a point between its centre of curvature and focus. The image will be formed at: A. the focus B. the centre of curvature C. a point between the focus and the centre of curvature D. a point beyond the centre of curvature **Answer:** d ## Q109. A car is moving with a high speed. Which energy does it possess? A. Frictional force B. Gravitational force C. Kinetic energy D. Potential energy **Answer:** c ## Q110. An object travels northwards with a constant velocity. The net force acting on the object will be _________. A. towards the south B. towards the east C. zero D. towards the north **Answer:** c ## Q111. When a ray of light travels from a denser medium to a rarer medium, the ray will: A. Slow down and bend away from the normal B. Speed up and bend towards the normal C. Slow down and bend towards the normal D. Speed up and bend away from the normal **Answer:** d ## Q112. The energy possessed by an object because of its position or shape is called________. A. Kinetic energy B. Potential energy C. Static energy D. Latent energy **Answer:** b ## Q113. The mass of an object on the Earth is 60 Kg. What is its mass on the Moon? A. 10 Kg B. 60 N C. 60 Kg D. 10 N **Answer:** c ## Q114. When an object is _______ of a convex lens, the nature of the image is enlarged, virtual and erect. A. Between F1 and O B. At 2F1 C. At F1 D. At infinity **Answer:** a ## Q115. The SI unit of Resistivity is : A. Ohm .m B. Ampere C. Ohm D. Joule **Answer:** a ## Q116. The product of Mass and Acceleration is ______. A. Pressure B. Velocity C. Force D. Thrust **Answer:** c ## Q117. The product of Mass and Velocity is called _______. A. Thrust B. Momentum C. Force D. Pressure **Answer:** b ## Q118. What is the SI unit of Pressure? A. Pascal B. Newton C. Dyne D. Joule **Answer:** a ## Q119. Work has _________. A. no direction and only magnitude B. no direction and no magnitude C. only direction and no magnitude D. both direction and magnitude **Answer:** a ## Q120. Which of the following is a use of ultrasonography? A. It is used to read X-rays B. It is used to dissect organs C. It is used to observe the advantages of medicines D. It is used to monitor the growth of a foetus inside the mother's womb **Answer:** d ## Q121. All forces have: A. Direction B. Magnitude C. Both Magnitude and Direction D. Density **Answer:** c ## Q122. What happens to the force between two objects if the masses of both the objects are tripled? A. Force will get two times B. Force will get three times C. Force will get same time D. Force will get nine times **Answer:** d ## Q123. A spherical mirror, whose reflecting surface is curved outwards, is called a : A. Convex mirror B. Simple mirror C. Plain mirror D. Concave mirror **Answer:** a ## Q124. Which of the following statements is true for the law of conservation of energy? A. Energy can only be created B. Energy is created as well as destroyed C. Energy is neither created nor destroyed D. Energy can only be destroyed **Answer:** c ## Q125. In a _______ circuit, the electricity has only one path to flow through. A. Series B. Incomplete C. Complete D. Parallel **Answer:** a ## Q126. ______ is/are radiation emitted by the Sun and responsible for the cause of cancer. A. Beta rays B. Alpha rays C. Gamma rays D. UV radiation **Answer:** d ## Q127. The centre of reflecting surface of a spherical mirror is a point called the _______ A. Radius B. Pole C. Focus D. Principal axis **Answer:** b ## Q128. If a constant force applied on an object is given as the product of force and distance moved by the object in the direction of force, then it is termed as: A. Work done B. Acceleration C. Impulse D. Retardation **Answer:** a ## Q129. A Voltimeter is used to measure _______. A. air resistance B. potential difference C. magnetic induction D. electric current **Answer:** b ## Q130. If the temperature increases, the speed of sound: A. Increases B. Decreases C. Becomes zero D. Becomes infinity **Answer:** a ## Q131. Which of the following is NOT a unit that measures temperature? A. Kelvin B. Pascal C. Fahrenheit D. Celsius **Answer:** b ## Q132. In which of the following is the velocity of sound is maximum at 25 degree centigrade? A. Brass B. Aluminium C. Steel D. Iron **Answer:** b ## Q133. Motion of a boy, sitting on a swing is______. A. Periodic B. Non-uniform C. Uniform D. Circular **Answer:** a ## Q134. When a body falls freely under gravity, then the work done by the gravity is______. A. Negative B. Zero C. Positive D. Infinity **Answer:** c ## Q135. The rate of change of work is _______. A. Power B. Energy C. Force D. Momentum **Answer:** a ## Q136. Potential energy = Mass × ______ × Height. A. Displacement B. Acceleration due to gravity C. Velocity D. Energy **Answer:** b ## Q137. ________ is the smallest unit of Power. A. Kilowatt B. Milliwatt C. Watt D. Megawatt **Answer:** b ## Q138. _______ cells converts solar energy into electrical energy. A. Photovoltaic B. Galvanic C. Motor D. None of the above **Answer:** a ## Q139. One fathom = _____ . A. 6 feet B. 12 meters C. 60 feet D. 6 meters **Answer:** a ## Q140. Mho is the SI unit of which of the following physical quantity? A. Impedance B. Luminous flux C. Inductance D. Electric conductance **Answer:** d ## Q141. Pick the odd one out. A. Meter B. Centimeter C. Kilometer D. Mile **Answer:** d ## Q142. Which type of mirror is used by dentists to see large images of patients teeth? A. Convex mirror B. Spherical mirror C. Plain mirror D. Concave mirror **Answer:** d ## Q143. Which colour deviates the least when light passes through the prism? A. Violet B. Blue C. Red D. Green **Answer:** c ## Q144. Which colour deviates the most when light passes through the prism? A. Violet B. Blue C. Red D. Green **Answer:** a ## Q145. Among various electrical safety devices, one based on the heating effect of electric current is called a : A. Fuse B. Circuit breaker C. Protective relay D. Surge protector **Answer:** a ## Q146. Which waves cannot be transmitted through vacuum? A. Light B. Heat C. Sound D. Electromagnetic **Answer:** c ## Q147. Which of the following is a mechanical wave? A. Radio waves B. X-rays C. Light waves D. Sound waves **Answer:** d ## Q148. A rader which detects the presence of an enemy aircraft uses: A. Light waves B. Radio waves C. Sound waves D. Ultrasound waves **Answer:** d ## Q149. The velocity of sound is maximum in : A. Air B. Liquid C. Metal D. Vacuum **Answer:** c ## Q150. To hear a clear echo, the minimum distance between the reflecting surface and the observer should be A. 25 cm B. 17 m C. 17.2 m D. 16.5 m **Answer:** c ## Q151. Which of the folowing has the longest wavelength? A. Infrared B. X-rays C. Visible rays D. Radio waves **Answer:** d ## Q152. Which one of the following does a TV remote control unit use to operate a TV set? A. Infrared B. X-rays C. Visible rays D. Ultraviolet **Answer:** a ## Q153. The Doppler's effect is applicable for A. Light waves B. Sound waves C. Space waves D. Both for Light waves and Sound waves **Answer:** d ## Q154. A device which converts electrical energy into mechanical energy is: A. Dynamo B. Transformer C. Electric motor D. Inductor **Answer:** c ## Q155. Fuse is based on the principle of : A. Chemical effect of electricity B. Mechanical effect of electricity C. Heating effect of electricity D. Magnetic effect of electricity **Answer:** c ## Q156. Which gas is filled in fluorescent tube? A. Neon B. Argon C. Sodium D. Nitrogen **Answer:** a ## Q157. The device used for converting AC to DC is called A. Inverter B. Rectifier C. Transformer D. Transmitter **Answer:** b ## Q158. Which among the following waves is used for communication by artificial satellites? A. Microwaves B. Radio waves C. Infrared D. Beta rays **Answer:** a ## Q159. The dimension of which of the following is the same as that of Impulse? A. Volume B. Momentum C. Torque D. Force **Answer:** b ## Q160. The splitting of white light into different colours in a prism is called: A. Reflection of light B. Scattering of light C. Refraction of light D. Dispersion of light **Answer:** d ## Q161. The snow on the mountains does not melt all at once when it is heated bt the Sun because: A. It becomes very hard B. It reflects most of the heat from the sun C. It has a low specific heat capacity D. It has a high latent heat of fusion **Answer:** b ## Q162. An ice block with a piece of lead embedded in it floats in water. If ice melts the water level A. Rises B. Falls C. Remains same D. Falls first and then rises **Answer:** b ## Q163. Which of the following rays is used in oven? A. X-rays B. UV radiation C. Microwaves D. Radio waves **Answer:** c ## Q164. Energy is continuously created in the Sun due to: A. Nuclear Fusion B. Nuclear Fission C. Radioactivity D. None of the above **Answer:** a ## Q165. Which set of conditions represents the easiest way to liquify a gas? A. Low temperature and high pressure B. High temperature and low pressure C. Low temperature and low pressure D. High temperature and high pressure **Answer:** a ## Q166. While catching a ball a player pulls down his hands to lower the A. Force B. Momentum C. Impulse D. Velocity **Answer:** b ## Q167. If the length of a simple pendulum is halved then its period of oscillation is A. Doubled B. Halved C. Increased by a factor D. Decrease by a factor **Answer:** d ## Q168. The different colours of different stars are due to the variation of A. Temperature B. Pressure C. Density D. Radiation from them **Answer:** a ## Q169. When a bottle of scent is kept open in a comer of a room its odour is felt in all parts of the room. This is due to the phenomenon of: A. Evaporation B. Vaporization C. Diffusion D. Sublimation **Answer:** c ## Q170. A passenger standing In a bus is thrown outward when the bus takes a sudden turn happens due to A. Ootward pull on him B. Inertia of motion C. Change in momentum D. Change in acceleration **Answer:** b ## Q171. When pressure is increased the melting point of ice A. Increases B. Does not change C. Decreases D. Depends on the impurity in the ice **Answer:** c ## Q172. Longitudinal waves cannot travel through A. Vacuum B. Solid C. Liquid D. Gas **Answer:** a ## Q173. Dynamo is a device for converting A. Heat energy into electrical energy B. Mechanical energy into electrical energy C. c)Magnetic energy into electrical energy D. Chemical energy Into electrical energy **Answer:** b ## Q174. Oil rises up the wick in a lamp because A. Oil is very light B. Of the diffusion of oil through the wick C. Of the surface tension phenomenon D. Of the capillary action phenomenon **Answer:** d ## Q175. Lamberts law is related to A. Reflection B. Refraction C. Interference D. Illumination **Answer:** d ## Q176. The mass energy relation is the outcome of A. Quantum theory B. General Theory of Relativity C. Field theory of Energy D. Special theory of Relativity **Answer:** d ## Q177. Danger signals are generally red as red light A. Is least bright B. Under goes least deviation C. Has lowest velocity D. Gives comfort to eye **Answer:** b ## Q178. An oil drop spreads over water because A. Oil is lighter than water B. Oil is more viscous C. Oil does not mix with water D. Surface tension of oil is much smaller than that of water **Answer:** d ## Q179. When the main switch of the house is put off it disconnects the A. Live wire only B. Live wire and the earth wire only C. Live wire and the neutral wire only D. Earth wire and the neutral wire **Answer:** c ## Q180. Twinkling of stars is due to the phenomenon of: A. Dispersion of light B. Total Internal reflection C. Atmospheric refraction D. Atmospheric reflection **Answer:** b ## Q181. A multimeter is used to measure A. Current B. Voltage C. Resistance D. All of the above **Answer:** d ## Q182. Which of the following is used to split white light Into different colours ? A. Glass slab B. Convex lens C. Concave mirror D. Prism **Answer:** d ## Q183. Nuclear reactors used to produce electricity are based on A. Nuclear Fusion B. Nuclear Fission C. Radioactivity D. Superconductivity **Answer:** b ## Q184. A fountain pen Works on the principle of A. Flow of liquid from higher to lower potential B. Capillary action C. Bernoullis principle D. Viscosity of liquid **Answer:** b ## Q185. Optical Fibre work on the principle of A. Scattering of light B. Total Internal Reflection C. Total Internal Refraction D. Reflection of light **Answer:** b ## Q186. The energy stored in a watch spring is A. Kinetic energy B. Potential energy C. Heat energy D. Chemical energy **Answer:** b ## Q187. The sensation of weightlessness in a spacecraft in an orbit is due to the A. Absence of gravity outside B. Aceleration in the orbit which is equal to the acceleration due to gravity outside C. presence of gravity outside but not inside the spacecraft D. fact that spacecraft in the orbit has ho energy **Answer:** b ## Q188. A parachute descends slowly whereas a stone dropped from the same height falls rapidly because A. Stone is heiver than parachute B. Special mechanisms are present in the parachute C. A parachute has a larger surface area and air resistance is more D. None of the above **Answer:** c ## Q189. Newtons first law of motion gives the concept of A. Energy B. Work C. Momentum D. Inertia **Answer:** d ## Q190. The reason for a swimming pool to appear less deep than the actual depth is A. Refraction B. Scattering C. Reflection D. Interference **Answer:** a ## Q191. The swing of a spinning cricket ball in air can be explained on the basis of A. Sudden change in wind direction B. Buoyancy of air C. Turbulence caused by wind D. Bernoulli's principle **Answer:** c ## Q192. Spectacles used for viewing 3D films have A. Convex lens B. Concave lens C. Polaroid's D. Bifocal lens **Answer:** c ## Q193. A boy sitting in an open car moving with the constant speed throws a ball straight up into the air. The ball falls A. Behind him B. In front of him C. Into his hand D. By his side **Answer:** a ## Q194. Velocity of sound in air does not change with the change of A. Temperature of air B. Pressure of air C. Moisture content in air D. Wind in the direction of propagation of sound **Answer:** b ## Q195. Ventilators are provided near the ceiling of the room because A. the exhaled warmer air rises up and goes out B. these provide cross ventilation in the room C. these provide some sunlight in the room D. these do not look nice in the lower part **Answer:** a ## Q196. The strongest force in nature is A. Electrical force B. Gravitational force C. Nuclear force D. Magnetic force **Answer:** c ## Q197. A falling drop of rain water acquires the spherical shape due to A. Viscocity B. Surface Tension C. Atmospheric pressure D. Gravitational fprce **Answer:** b ## Q198. The weakest of all fundamental forces is A. Gravitational force B. Electrostatic force C. Magnetic force D. Nuclear force **Answer:** a ## Q199. A mirage occurs because of A. Reflection occurs by hot ground B. Total Internal Reflection by layers of air C. Interference of light D. Diffraction of light **Answer:** b ## Q200. A soap bubble shows colours when illuminated with white light. This is due to A. Diffraction B. Polarization C. Interference D. Reflection **Answer:** c ## Q201. A person is hurt on kicking a stone due to A. Inertia B. Velocity C. Reaction D. Momentum **Answer:** c ## Q202. If a boy sitting in a train which is moving at a constant velocity throws a ball straight up into the air the ball will A. Fall infront of him B. Fall behind him C. Fall into his hand D. None of the above **Answer:** c --- Source: https://www.easy2crack.com/mcqs/physics/unit-1-physics-quiz-uAqXUnuh Site: https://www.easy2crack.com · Machine index: https://www.easy2crack.com/llms.txt · MCP: https://www.easy2crack.com/mcp