Six students carry out an investigation to determine their powers when running up stairs - Edexcel - GCSE Physics - Question 6 - 2022 - Paper 1

The unit for work done is Joules (J).

To calculate the weight of student B, we can rearrange the work done formula:

$Work = Weight \times Height$

Given that work done by student B is 1960 J and the vertical height (Distance B) is 4.0 m,

We find:

$Weight = \frac{Work}{Height} = \frac{1960 \text{ J}}{4.0 \text{ m}} = 490 ext{ N}$

Therefore, the estimated weight of student B is 490 N.

Using the formula for power which is defined as:

$Power = \frac{Work}{Time}$

we rearrange this to find time:

$Time = \frac{Work}{Power}$

For student C, the work done is 2040 J and the estimated power is 425 W:

$Time = \frac{2040 \text{ J}}{425 \text{ W}} \approx 4.8 \text{ s}$

Thus, student C takes approximately 4.8 seconds.

To calculate the average power of the three students, we first sum their individual powers:

$440 ext{ W} + 436 ext{ W} + 425 ext{ W} = 1301 ext{ W}$

Then, we divide this sum by the number of students:

$Average \ Power = \frac{1301 ext{ W}}{3} = 434 ext{ W}$

Hence, the average power of the students is 434 W.

A significant source of error in this investigation could be the estimation of weight by students, as it may not be accurate.

This error can be reduced by measuring the actual weight using calibrated scales instead of relying on self-estimation.