Most Important Physics Mcqs 81- The resistance of a wire depends on: A. Its lengthB. Its cross-sectional areaC. The material of the wireD. All of the above View Answer Answer : D. All of the above Description 82- A device used to convert mechanical energy into electrical energy is: A. GeneratorB. MotorC. TransformerD. Rectifier View Answer Answer : A. Generator Description 83- The absolute zero temperature is: A. 0°CB. 273.15°CC. -100°CD. -273.15°C View Answer Answer : D. -273.15°C Description 84- Heat transfer that requires no medium is: A. ConductionB. ConvectionC. RadiationD. None of these View Answer Answer : C. Radiation Description 85- The first law of thermodynamics is a restatement of: A. Conservation of massB. Conservation of chargeC. Conservation of energyD. Conservation of momentum View Answer Answer : C. Conservation of energy Description 86- Which of the following expands the most when heated? A. SolidsB. LiquidsC. GasesD. All expand equally View Answer Answer : C. Gases Description 87- The lens used to correct myopia (short-sightedness) is: A. Convex lensB. Concave lensC. Cylindrical lensD. Bifocal lens View Answer Answer : B. Concave lens Description 88- The bending of light when it passes from one medium to another is called: A. RefractionB. ReflectionC. DiffractionD. Dispersion View Answer Answer : A. Refraction Description 89- A rainbow is formed due to: A. ReflectionB. RefractionC. DispersionD. All of these View Answer Answer : D. All of these Description 90- A convex lens is also known as a: A. Diverging lensB. Converging lensC. Cylindrical lensD. Planar lens View Answer Answer : B. Converging lens Description 91- The photoelectric effect was explained by: A. Albert EinsteinB. Isaac NewtonC. Nikola TeslaD. James Clerk Maxwell View Answer Answer : A. Albert Einstein Description 92- The charge of an electron is: A. 0 CB. +1.6 × 10⁻¹⁹ CC. -1.6 × 10⁻¹⁹ CD. +9.1 × 10⁻³¹ C View Answer Answer : C. -1.6 × 10⁻¹⁹ C Description 93- The unit of radioactive decay is: A. TeslaB. HertzC. NewtonD. Becquerel View Answer Answer : D. Becquerel Description 94- The energy of a photon is given by: A. E = mc²B. E = hfC. E = mv²D. E = ½ mv² View Answer Answer : B. E = hf Description 1 2 3 4 5
