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, the child is applying force to the tricycle, causing it to move. This is an example of mechanical work. Work involves transferring energy from one object to another. In this case, the child is exerting force to move the tricycle, and the energy from the child (in the form of muscular energy) is transferred to the tricycle.
As the tricycle moves, it gains kinetic energy, which is the energy of motion. The amount of kinetic energy depends on the mass of the tricycle and its velocity. The formula for kinetic energy is: KE=12mv2KE = \frac{1}{2}mv^2
where m is the mass of the tricycle and v is its velocity. As the child pushes the tricycle, the velocity increases, and so does the kinetic energy of the tricycle.
The child does not destroy energy in the process; instead, the child is transferring energy. Energy cannot be destroyed, only transformed or transferred. Therefore, options A, C, and D are incorrect because they imply either the creation or destruction of energy, which contradicts the law of conservation of energy. Energy is always conserved and can only change forms.
In conclusion, when the child pushes the tricycle, the tricycle gains kinetic energy as a result of the work done by the child, which is why the correct answer is B: tricycle gained energy.