20. Which of the following statements gives a correct idea about the relationship between energy
A child pushes a heavy door without success
C. An erupting volcano releases much energy
B. Ice absorbs energy as it melts
D. Energy is the ability to exert force on an object and makes it move
21. How much power is required to do 75 J of work in 5s?
A 15 Watt
B. 170Watt
C. 375Watt
D. 1500Watt
22. Which type of energy does flowing water possess?
A Thermal energy
B. Kinetic energy
C. Potential energy
D. electrical energy
23. A car has 3000J of Kinetic energy, what will be its kinetic energy if its speed is doubled?
A Doubled
B. Tripled
C. Quadrupled
D. Reduced to 12 24. When an object is lifted 10m, it gains a certain amount of potential energy. If the same object is lifted 20m, its PE is B. The same C. Twice as much D. Four times as much A. Less 25. A car has a mass of 1000kg and a speed of 60Kph and car b has a mass of 2000kg with a speed of 30kph. The KE of car Ais C. Twice that of car A is?
A Half that of car
D. Four times that of car B
B. Equal that of car B
26. How does an object gain potential energy (PE)?
C. by cooling to a lower temperature
A. By melting
D. by being raised above the ground
B. By gaining speed​