In one day, 2 500 000 kg of water passes through the hydroelectric generator - AQA - GCSE Physics - Question 4 - 2023 - Paper 1

To find the mean change in vertical height, we use the formula for gravitational potential energy:

$E_p = mgh$

Where:

• $E_p$ is the gravitational potential energy (in joules)
• $m$ is the mass (in kg)
• $g$ is the gravitational field strength (9.8 N/kg)
• $h$ is the height (in meters)

1. Convert the energy from MJ to J: $367.5 ext{ MJ} = 367.5 imes 10^6 ext{ J}$

2. Substituting the values into the equation: $367.5 imes 10^6 = 2 500 000 imes 9.8 imes h$

3. Rearranging the formula to solve for $h$: $h = \frac{367.5 imes 10^6}{2 500 000 imes 9.8}$

4. Calculating $h$: $h \approx 15 ext{ m}$

Thus, the mean change in vertical height is 15 m.