Which does heat represent?
A. transfer of kinetic energy
B. transfer of thermal energy
C. transfer of potential energy
D. transfer of temperature
How does a pulley make it easier to load cargo onto a cargo ship?
A. The pulley increases the force needed to lift the load by moving it over a shorter distance. It also changes the direction of the force. As the input force is applied upward, the output force is exerted downward.
B. The pulley reduces the force needed to lift the load by moving it over a longer distance. It also changes the direction of the force. As the input force is applied downward, the output force is exerted upward.
C. The pulley reduces the force needed to lift the load by moving it over a shorter distance. It also changes the direction of the force. As the input force is applied upward, the output force is exerted downward.
D. The pulley increases the force needed to lift the load by moving it over a longer distance. It also changes the direction of the force. As the input force is applied downward, the output force is exerted upward.
Which describes the difference between a bowling ball sitting in the rack waiting to be used and the bowling ball knocking pins down?
A. In the rack, the bowling ball has no energy at all. As it knocks down the pins the energy is 75% kinetic and 25% potential.
B. In the rack and when knocking down pins, the potential energy and the kinetic energy of the bowling ball are equal.
C. In the rack, the bowling ball has only potential energy. As it knocks pins down, its potential energy has decreased, while its kinetic energy has increased.
D. In the rack, the bowling ball has only kinetic energy. As it knocks pins down, its potential energy has increased, while its kinetic energy has decreased.