Given: Heat Qout means useful work = 2800 J
Heat Qin = 8900 J
Required; Efficiency = ?
Formula: Efficiency = Qout/Qin = x 100%
= 2800 J/8900 J = 0.3146 X 100 %
Efficiency = 31.46%
Answer:
The answer is choice (3)
Explanation: Land materials do require more energy than water to raise their temperature by one degree, hence why water gets heated a lot easier than something like wood.
Answer: A Bowling Ball
Explanation:
A body possess kinetic energy due to virtue of its motion. It depends on the mass of the body and the speed with which it is travelling.
K.E = 0.5 mv²
K.E. ∝ m
It is given that the marble, bowling ball, basketball and baseball all are rolling with the same speed. This means that the greatest energy would be possessed by the body having greatest mass.
On an average the mass of a marble is about 50 g, mass of a bowling ball is 750 g, mass of baseball is 150 g and mass of basketball is 600 g. Since the mass of a Bowling ball is the greatest, it would possess the greatest kinetic energy.
