Welcome to your Energy, Work and Power(Senior Class Physics Study by Topics) NAME EMAIL PHONE NUMBER 1. A person jumps to the ground from a platform 10 feet high. Which of the following is true? The person's kinetic energy at the instant they jump is approximately double their potential energy the instant they land.The person's potential energy at the instant they jump is approximately equal to their kinetic energy the instant they land.The person has less potential energy at the top of the platform than in the air.The person has more kinetic energy before they jump than after they jump.2. A gardener pushes a lawn roller through a distance of 20m. If he applies a force of 20kg weight in a direction inclined at 60° to the ground, find the work done by him. (g=9.8m/s2)250J2514J400J1960J3. A motorbike engine can develop a power of 90000 W in order to keep a constant velocity of 30 m/s. What is the pushing force?3000 N300 N30 N30000 N4. If you push on a wall with a force of 30 N, then ______________. The wall cannot be forced.The wall pushes on you with a force of 30 N.The wall moves back 3 cm.You are pulled towards the wall.5. A machine gun fires 60 bullets per minute, with a velocity of 700m/s. If each bullet has a mass of 50g, find the power developed by the gun.122.5W1225W12250W122W6. A person is holding a bucket by applying a force of 10N. He moves a horizontal distance of 5m and then climbs up a vertical distance of 10m. Find the total work done by him?150J50J200J100J7. Collision between two carom coins is an example for ____Oblique collisionElastic collisionPerfectly inelastic collisionInelastic collision8. A block with a mass of m crosses a rough horizontal surface at a constant speed of v. The coefficient of kinetic friction between the block and the surface isµ. How much power must be produced in order to overcome the friction force?µmgµmgvmgµg9. When a light body collides with a massive body at rest _____The light body rebounds after the collisionThe massive body rebounds after the collisionNo reaction happensThe light body Remains at rest10. A truck drives slams on the brakes of a moving truck with a constant velocity v, as a result of his action the truck stops after traveling a distance d. If thedriver had been traveling with twice the velocity, what would be the stopping distance compared to the distance in the first trial?Half as muchTwo times greaterOne-quarter as muchFour times greater11. The type of energy possessed by a simple pendulum, when it is at the mean position is:Sound energyKinetic energyPotential energyKinetic + Potential energy12. Which of the following is NOT a consequence of "The Law of Conservation of Energy"?Potential Energy can never be greater than Kinetic EnergyThe energy in a closed system is always constantIt is not necessary to use Kinematics to discover the velocity of an object accelerated by gravity if you know it's initial Potential Energy and its mass.The Kinetic Energy of a dropped object at the instant it hits the ground is roughly equal to the potential energy of the object at the instant it was dropped13. A feather and a coin dropped in a vacuum fall with equal _____. ForcesMomentaAccelerationsKinetic energies14. What happens to the total energy of a moving object if all the applied forces are conserved?It increasesIt decreasesThe velocity is required to answer this questionIt remains constant15. Which of the following is an example of inelastic collision?Collision between two vehiclesCollision between glass ballsCollision between two railway compartmentsA bullet fired into a wooden block16. Which of the following is not a unit for power?Newton-meter per secondHorsepowerJoule – secondWatt17. If a mass is at rest, what must be applied to cause it to move? ForceSpeedVectorsKilograms18. When a body falls freely under gravity, then the work done by the gravity is ________InfinityPositiveZeroNegative19. When an object is lifted 10 meters, it gains a certain amount of potential energy. If the same object is lifted 20 meters, its potential energy is ______. Less.Four times as muchTwice as much.The same20. Which one of the following is not the unit of energy?KilowattKilowatt hourJouleNewton meter21. How many Joules of energy are in one kilowatt-hour? 60 kilojoules3.6 megajoules1 J60 J22. If you have to push a car forward, what are the forces acting on you? Only gravity.No forces act on you.Your own muscles push you down.The car pushes back on you, gravity pulls you down, the ground pushes up on you, and friction on your shoes pushes forward on you.23. A moving hammer drives a nail into the wood. It has kinetic energy.FalseTrue24. A ball is projected into the air with 100 J of kinetic energy which is transformed to gravitational potential energy at the top of its trajectory. When it returns to its original level after encountering air resistance, its kinetic energy is _____.100 J.Not enough information given.Less than 100 J.More than 100 J.25. A man of mass 50 kg jumps to a height of 1 m. His potential energy at the highest point is (g = 10 m/s2):5000 J5 J50 J500 J26 out of 25Time is Up!
