Question

Point B represents a distance half-way down the ramp. If the ball rolls down the ramp, how much potential energy has been converted to kinetic energy at point B?
Responses
A 0 J0 J
B 25 J25 J
C 50 J50 J
D 100 J

Answer 1

To determine how much potential energy (PE) has been converted to kinetic energy (KE) by point B, we need to understand the energy conversion that occurs as the ball rolls down the ramp.

Potential energy is given by the formula:

\[ PE = mgh \]

where:
- \( m \) = mass of the ball
- \( g \) = acceleration due to gravity (approximately \( 9.81 \, \text{m/s}^2 \))
- \( h \) = height of the ramp

As the ball rolls down the ramp, its potential energy is converted into kinetic energy. At point B, being halfway down the ramp means the ball has descended half the height of the ramp.

If the total potential energy at the top of the ramp is given to be \( 100 \, J \) (assuming that's the total amount of potential energy at the height), at point B (halfway down), it would have lost half of that potential energy.

Thus:

\[ \text{Potential Energy lost at point B} = \frac{100 \, J}{2} = 50 \, J \]

This means that at point B, \( 50 \, J \) of potential energy has been converted to kinetic energy.

Therefore, the correct answer is:

**C 50 J**