In the diagram below, two objects of the same size and mass are released from rest at the starting position. Object 1 was released before Object 2 was released. The diagram below shows the positions of Objects 1 and 2 a short time after both were released.

Question

Which object in the figure has the least amount of kinetic energy?

Object 1
Object 1

Object 2
Object 2

Both objects have the same amount of kinetic energy.
Both objects have the same amount of kinetic energy.

Neither object has any kinetic energy.

Answer 1

To determine which object has the least amount of kinetic energy, we need to consider how kinetic energy is defined and the situation of the objects.

Kinetic energy (KE) is given by the formula:

\[ KE = \frac{1}{2} mv^2 \]

where \( m \) is the mass of the object and \( v \) is its velocity.

In this scenario, Object 1 has been released before Object 2, meaning it has had more time to accelerate due to gravity. Consequently, Object 1 is likely to be moving faster than Object 2. Object 2, having been released later, has had less time to accelerate and therefore would have a lower velocity.

Given that both objects have the same mass, we can compare their kinetic energies:

• Object 1, having a greater velocity, will have greater kinetic energy.
• Object 2, with a lesser velocity, will have less kinetic energy.

Therefore, it can be concluded that Object 2 has the least amount of kinetic energy among the two.