1. Power is the rate of doing work.   True   False   2. _______ is the capacity to do work.   Pressure   Force   Energy   Hint Half-n-half Clue   3. 'Energy can neither be created nor destroyed' is a statement of the   Law of Conservation of Energy   Law of Conservation of Matter   Law of Conservation of Electric Charges   Half-n-half Clue   4. If an engine does 300 J of work in 5 seconds, its average power is   1500 W   60 W   295 W   305 W   Half-n-half Clue   5. The energy losses from machines are mostly dissipated as sound energy.   True   False   6. A carton is pulled along the ground for a distance of 9 m. If the average frictional force is 56 N, then the work done is   9 J   4536 J   56 J   504 J   Half-n-half Clue   7. Efficiency of a machine equals   Work Input / (Work Input + Work Output) × 100 %   Work Output / (Work Input + Work Output) × 100 %   Work Output / Work Input × 100 %   Work Input / Work Output × 100 %   Half-n-half Clue