Question

distinguishing between potential and kinetic energy
at which position, a or b, is the potential energy of the swing the greatest?
as the swing moves from point b to point a, which form of energy is increasing, kinetic or potential?

Explanation:

First Question: At which position, A or B, is the potential energy of the swing the greatest?

Step1: Recall PE formula

Potential Energy (PE) due to gravity: $PE = mgh$, where $m$ is mass, $g$ is gravity, $h$ is height.

Step2: Compare heights of A and B

From the diagram, position B is at a greater height than position A (the vertical arrow for B is longer than for A).

Step3: Determine PE based on height

Since $PE \propto h$ (for constant $m, g$), greater height means greater PE. So B has greater PE.

Step1: Analyze energy change with motion

As the swing moves from B (higher) to A (lower), height decreases. So PE ($mgh$) decreases.

Step2: Apply energy conservation

Total mechanical energy (PE + KE) is conserved (ignoring air resistance). If PE decreases, KE must increase (since $PE + KE = \text{constant}$).

Step3: Conclude the increasing energy

Thus, kinetic energy (KE) is increasing as the swing moves from B to A.

Answer:

B

Second Question: As the swing moves from point B to point A, which form of energy is increasing, kinetic or potential?