A motor lifts a mass of 50000 kg through a vertical height of 25 m - Edexcel - A-Level Physics - Question 8 - 2023 - Paper 1

The power of the motor is given as 700 kW, which is equivalent to:

$P = 700 \times 10^3 \, W$

Using the formula for power, defined as work done over time:

$P = \frac{W}{t}$,

we can rearrange this to solve for time $t$:

$t = \frac{W}{P}$.

Substituting the work done (which is equal to GPE) and the power:

$t = \frac{12262500 \, J}{700 \times 10^3 \, W} = 17.5 \, seconds$.

Thus, the time taken to lift the mass can be found from the options provided.

From the calculations, we see that the correct answer corresponds to the formula used for GPE in option B:

$\frac{50000 \times 9.81 \times 25}{700000}$,

which, when calculated, yields the time taken in seconds.