Which situation best demonstrates the law of conservation of energy?
a
the potential energy of a ball being dropped from a cliff being converted to kinetic energy
b
ice water transforming into liquid water when it absorbs heat energy
c
batteries being able to store potential energy over a long period of time
d
a long distance runner conserving her energy to sprint at the end of the race
Option (a) - The potential energy of a ball being dropped from a cliff being converted to kinetic energy best demonstrates the law of conservation of energy. By dropping the ball, the potential energy is converted into kinetic energy, and the total amount of energy in the system remains constant. This is because energy cannot be created or destroyed, only transferred or transformed from one form to another.
The situation that best demonstrates the law of conservation of energy is option a: the potential energy of a ball being dropped from a cliff being converted to kinetic energy.
Explanation:
The law of conservation of energy states that energy cannot be created or destroyed, but it can be transformed from one form to another. In this case, the ball has potential energy due to its position on the cliff, which is transformed into kinetic energy as it falls. The total amount of energy remains the same, only changing from potential to kinetic.
Option b describes a phase change, which involves the transfer of heat energy to change the state of a substance, but it doesn't fully demonstrate the law of conservation of energy.
Option c mentions the storage of potential energy in batteries, but it doesn't involve any transformation or transfer of energy from one form to another, making it less representative of the law of conservation of energy.
Option d mentions a long distance runner conserving her energy to sprint at the end of the race, which involves the management of energy, but it doesn't explicitly demonstrate the conservation of energy as described by the law.
a) The potential energy of a ball being dropped from a cliff being converted to kinetic energy best demonstrates the law of conservation of energy.
According to the law of conservation of energy, energy cannot be created or destroyed but can only be converted from one form to another. In this situation, as the ball is dropped from the cliff, its potential energy (due to its height above the ground) is converted into kinetic energy (motion) as it falls. The total amount of energy remains constant, but it changes its form from potential to kinetic energy.