A child pushes her tricycle. It can be said the
A
child created energy.
B
tricycle gained energy.
C
child destroyed energy.
D
tricycle destroyed energy.
The correct answer and explanation is:
The correct answer is B: tricycle gained energy.
When the child pushes the tricycle, she applies a force to it. This force causes the tricycle to accelerate, gaining kinetic energy. The child transfers energy from her muscles (through work) to the tricycle. The energy is not created or destroyed; it is simply transferred and transformed from one form to another. The child’s muscles provide the energy for the motion of the tricycle.
The process of transferring energy in this way is governed by the law of conservation of energy, which states that energy cannot be created or destroyed, only converted from one form to another. In this case, the child’s chemical energy (from food) in her muscles is converted into mechanical energy, which is transferred to the tricycle, making it move. The tricycle gains this mechanical energy in the form of kinetic energy as it begins to move.
Therefore, the energy the child uses is not destroyed, nor is it “created.” Rather, it is transferred from the child to the tricycle. This is a key concept in physics: when a person pushes an object, the energy used to apply the force is transferred to the object, causing it to move and gain energy.
It’s important to note that the amount of energy gained by the tricycle depends on the force exerted and the distance over which it is applied, as described in the work-energy principle.