Multiple Choice Questions Chapter 4 Work and Energy l First Year Physics Federal Board KPK Syllabus скачать в хорошем качестве

Multiple Choice Questions Chapter 4 Work and Energy l First Year Physics Federal Board KPK Syllabus

Choose the best possible answer You push a heavy crate down at a ramp at a constant velocity. Only four forces act on the crate. Which force does the greatest magnitude of work on the crate? A. The force of friction B. The force of gravity C. The normal force D. The force you pushing The force constant of a wire is k and that of the another wire is 3k when both the wires are stretched through same distance, if work done are W1 and W2, then A. W2=W1 B. W2=9W1 C. W1=3W2 D. W2=3W1 Escape velocity on the surface of the earth is 11.2kms-1. If the mass of the earth increases to twice its value and the radius of the earth becomes half the escape velocity is A. 5.6kms-1 B. 11.2kms-1 C. 22.4kms-1 D. 33.6kms-1 An example of non-conservative force is: A. Electric force B. Gravitational force C. Frictional force D. Magnetic force When the speed of your car is doubled, by what factor does its kinetic energy increase? A. √2 B. 2 C. 4 D. 8 One horse power is given by: A. 746W B. 746kW C. 746MW D. 746GW Work is said to be negative when F ⃗ and d ⃗ are: A. Parallel B. Anti-parallel C. Perpendicular D. at 45o Two bodies of masses m1 and m2 have equal momentum their kinetic energies E1 and E2 are in the ratio A. √(m_1 ):√(m_2 ) B. m_1:m_2 C. m_2:m_1 D. √(m_1^2 ) √(m_2^2 ) The atmosphere is held to the earth by A. winds B. Gravity C. Clouds D. The rotation of Earth If momentum is increased by 20% then K.E increases by A. 44% B. 55% C. 66% D. 77% If the K.E of a body becomes four times of the initial value, then new momentum will A. Become twice its initial value B. Become three times, its initial value C. Become four times its initial value D. Remains constant Two bodies with kinetic energies in the ration of 4:1 are moving with equal linear momentum. The ratio of their masses is A. 1:2 B. 1:1 C. 4:1 D. 1:4 A body of mass 5kg is moving with a momentum of 10kgms-1. A force of 0.2N acts on it in the direction of motion of the body for 10s. the increase in its kinetic energy is A. 2.8J B. 3.2J C. 3.8J D. 4.4J If force and displacement of particle in the direction of force are doubled. Work would be A. Double B. times C. Half D. ¼ times