Which of these would be a typical speed for a racing cyclist travelling down a steep straight slope? A 0.2 m/s B 2 m/s C 20 m/s D 200 m/s A cyclist travels down a slope - Edexcel - GCSE Physics - Question 6 - 2019 - Paper 1

To calculate the change in gravitational potential energy (GPE), we use the formula:

$\Delta GPE = m \times g \times h$

Where:

• $m = 75 \, \text{kg}$ (mass of the cyclist)
• $g = 10 \, \text{N/kg}$ (gravitational field strength)
• $h = 20 \, \text{m}$ (height of the slope)

Substituting the values, we get:

$\Delta GPE = 75 \, \text{kg} \times 10 \, \text{N/kg} \times 20 \, \text{m}$

Evaluating this gives:

$\Delta GPE = 15000 \, \text{J}$

To find the distance travelled by the aircraft during acceleration, we use the formula:

$x = \frac{v^2 - u^2}{2a}$

Where:

• $v = 80 \, \text{m/s}$ (final speed)
• $u = 0 \, \text{m/s}$ (initial speed)
• $a = 4 \, \text{m/s}^2$ (acceleration)

Substituting the values, we have:

$x = \frac{(80)^2 - (0)^2}{2 \times 4}$

Calculating gives:

$x = \frac{6400}{8} = 800 \, \text{m}$