10. The loss of potential energy is 147 J.
11. When a body falls freely, its head is immersed in water because the water exerts an upward buoyant force that counteracts gravity, causing the body to float or partially submerge depending on density.
12. The kinetic energy is 1568 J.
13. The velocity is 19.8 m/s.
14. The power is 1225 W.
15. The work done is 392 J.
16. The efficiency is 80%.
17. The work done is 1000 J.
18. The work done is 5000 J.
19. The power is 500 W.
20. The work done is 6000 J.
21. The work done is 3000 J.
22. The work done is 1000 J.
23. The work done is 2000 J.
24. The work done is 1200 J.
25. The work done is 300 J.
26. The work done is 1500 J.
27. Doubling the mass doubles the kinetic energy; doubling the velocity quadruples the kinetic energy.
28. The relationship is direct: more commercial use means higher unit cost due to increased demand and resource allocation.
29. The power is 1500 W.
30. The power is 750 W.
31. The danger arises from the large momentum and high kinetic energy, which can cause severe damage upon impact.
32. The average power is 500 W.
33. The work done is 2000 J.
34. The work done is 1500 J.
35. The work done is 1000 J.
36. The work done is 2000 J.
37. The work done is 3000 J.
38. The work done is 1000 J.
Parent Tip: Review the logic above to help your child master the concept of work force and power worksheet.
