Question

Use the table of information to answer the question fruits watermelon A mass kilograms 4 speed (m/s) 2 fruit watermelon B mass kilograms 4 speed (m/s) to watermelons fall off a kitchen counter The masses and speeds of the fruits are in the table How do the kinetic and/or the potential energies of the fruit compare A both fruits have only potential energy and no kinetic energy

Answer 1

To determine the kinetic and potential energies of the watermelons as they fall off a kitchen counter, we need to understand the concepts of kinetic energy (KE) and potential energy (PE).

1. **Kinetic Energy (KE)** is given by the formula:
\[
KE = \frac{1}{2} mv^2
\]
where \( m \) is the mass and \( v \) is the speed of the object.

2. **Potential Energy (PE)** is given by the formula:
\[
PE = mgh
\]
where \( m \) is the mass, \( g \) is the acceleration due to gravity (approximately \( 9.81 \, \text{m/s}^2 \)), and \( h \) is the height above the ground.

Based on the information provided in your question about the two watermelons:

- Watermelon A: mass = 4 kg, speed = 2 m/s
- Watermelon B: mass = 4 kg, speed = 2 m/s

### At the moment they fall off the kitchen counter:

1. **Potential Energy (PE):** Both watermelons will have potential energy due to their height above the ground (assuming they are at the same height).

2. **Kinetic Energy (KE) of Watermelon A:**
\[
KE_A = \frac{1}{2} \times 4 \, \text{kg} \times (2 \, \text{m/s})^2 = \frac{1}{2} \times 4 \times 4 = 8 \, \text{J}
\]

3. **Kinetic Energy (KE) of Watermelon B:**
\[
KE_B = \frac{1}{2} \times 4 \, \text{kg} \times (2 \, \text{m/s})^2 = \frac{1}{2} \times 4 \times 4 = 8 \, \text{J}
\]

### Conclusion:
- Both watermelons have **kinetic energy** equal to 8 J when they are in motion (assuming they are moving at the speed of 2 m/s).
- Additionally, they also have **potential energy** since they are at a height above the ground before falling.

Therefore, the correct comparison is that **both fruits have both kinetic energy (due to their speed) and potential energy (due to their height)** while they are on the kitchen counter, not just potential energy.