Justice Eliezer Delos Santos National High School 1011 C. De Leon St. Boundary of Ugong and Gen. T. De Leon, Valenzuela City Score: 55 SUMMATIVE TEST # 2 Name:___________________________________________ Work, Power and Energy Section:__________________________________________ Date:___________________________ Teacher:_________________________ DIRECTIONS: Choose the letter of the best correct answer. Use CAPITAL LETTERS. Strictly NO ERASURES! 1. Which of the following equations may NOT be used to calculate the magnitude of work done? A. (Force) (displacement) C. (Weight) (height) B. (Power) (time) D. (mass) (acceleration) 2. What happens to the gravitational potential energy of an object if you bring it higher with respect to the ground? A. decreases B. increases C. decrease and increases D. nothing happens 3. Which is equivalent to 1 watt? A. kg.m/s B. kg.m2/s3 C. kg/s D. kg. m/s2 4. For work to be done, which of the following conditions must be met? I. A net force must act on the object II. The object must move perpendicular to the direction of the force III. The object has to move a certain distance A. I only B. I and III C. II and III D. I, II and III 5. A man pushes a wall with a force of 25N for 2seconds. If the wall does not move, how much work in joules is done by the man? A. 50 J B. 12.5 J C. 0.16 J D. 0 6. What are the factors needed to calculate the magnitude of potential energy acquired by any object brought to a certain height? I. Gravity II. Weight III. Vertical height IV. Mass A. I, II and III B. II, III, and IV C. I, II and IV D. I, III, and IV 7. What are the ways by which energy can be measured? A. joules B. Newton. meter C. kg.m/s2.m D. All of the above 8. Which of the following objects possess potential energy? A. food B. gasoline C. stretched spring D. All of these ***For numbers 9- 15, Write A if the following situations is a Potential Energy (P.E) transformed into Energy (K.E), Write B if NOT. 9. Twisted Rubber band to Rolling Toy 10. A stone thrown vertically upward 11. A person jumping up and down on a trampoline 12. A boy climbing up a ladder 13. A chandelier falling from the ceiling 14. A large stone on top of the hill slips and roll down the hill that hits plants and trees 15. Water behind a dam, when released, make the turbine rotates. Kinetic 16. Which of the following quantities may be used to calculate power? I. Time II. Newton III. Work IV. Joule A. I and II B. II and III C. III and IV D. I and III 17. In the diagram, the potential energy of load M1 (relative to the ground) is A. more than that of m2 M1=5kg B. equal to that of m2 M2= 5kg C. less than that of m2 H= 10m H = 5m D. equal to zero 18. Which is described as the capacity to do work? A. energy B. Work C. power D. Force 19. Which of the following shows an activity where NO work is done? A. A girl pushing her cart along a smooth surface C. A man lifting a box on a table B. A man pushing a ten-wheeler truck D. A girl pushing a chair to the right 20. What refers to the energy stored in elastic, stretchable, or compressible material like rubber band and springs? A. Power B. Kinetic Energy C. Elastic Potential Energy D. Gravitational Potential Energy 21. When a car’s speed is doubled, its kinetic energy is… A. twice as large C. four times as large B. half as large D. four times less 22. As an object falls from a cliff, A. the Kinetic energy increases C. the kinetic energy increases as the potential energy decreases B. the Potential energy increases D. the kinetic energy decreases as the potential energy increases 23. Which of the following situations has Work? A. Carrying your schoolbag while walking. B. Lifting a 1.5kg book from the lowest shelf in a cabinet to the fourth shelf 2m higher. C. Holding a food tray with your hand while walking. D. A mango fruit on the branch of a tree 24. The higher the object from the ground… A. The greater is its Potential Energy C. stable Potential Energy B. The lesser is its Potential Energy D. Nothing will happen II. Write the correct UNITS for the following quantities: Force Mass 1.____________ 2.___________ Work Kinetic Energy 5.____________ 6.___________ Acceleration 3.___________ Potential Energy 7.___________ Distance 4.__________ Power 8. __________ III. Write the FORMULA for the following: Force 1.___________ Work 2.___________ Kinetic Energy 3.___________ Potential Energy 4.___________ Power 5. ____________ IV. Matching Type. Write the letters of the correct answer. Column A __1. It is the capacity to do work __2. It is a method of transferring energy __3. It is the energy in motion __4. It is the stored energy of position at rest __5. It is the energy acquired by an object by the virtue of its height above the earth. __6. It is the energy stored in elastic materials __7. It is the speed of work __8. It is the distance in a given direction Column B a. Force b. Work c. Gravitational Potential Energy d. Elastic Potential Energy e. Energy f. Power g. Displacement h. Kinetic Energy i. Potential Energy V. TRUE or FALSE _______1. When work is done by an object it gains energy. _______2. When work is done on an object it loses energy _______3. The energy of an object enables it to do work. _______4. The more massive an object is, the greater its Potential energy _______5. The higher the object on the ground, the lesser its Potential Energy _______6. The shorter the time require to do the work, the greater its power VI. Solve for the following. Choose the letter of the correct answer. (2pts each) 1. Calculate the power output in watts of an 80kg man that climbs a flight of stairs 3.8m high in 4seconds. A. 744.8 watts B. 76 watts C. 1216 watts 2. A 98 kg basketball player runs at a speed of 7m/s. What is his kinetic energy? A. 686 J B. 14 J C. 2401 J 3. Calculate the work done when a crate was pushed along the floor by a man with a force of 500N through a distance of 6meters. A. 83.33 J B. 3000N C. 3000J 4. Determine the Potential energy of a 0.5kg object when it is raised 0.75m from the floor. A. 3.68 J B. 7.35 J C. 0.375J 5. A net force of 20000N is used to move a motorboat at a constant speed of 2.8m/s. How much power is developed? A. 7142.85watts B. 56000 watts C. 200 watts VI. Problem Solving: 1. Find the potential energy gained by a 50000kg train after climbing a 20m hill. 2. A bullet moves with a velocity of 600m/s and has gained a kinetic energy of 900J. Compute for its power. 3. What power in watts is employed in lifting a 50kg weight to a height of 20m in 60seconds? 4. A 62kg shell is shot from a cannon. a. What is the gravitational potential energy if the shell reaches a 450m height? b. What is the change in potential energy when the shell falls to the height of 300m? 5. A force of 8500N is needed to push a stranded car along the highway. The automechanic and the driver push the car 40m. How much work is done? GOD BLESS!!!