A student lifts a toy car from a bench and places the toy car at the top of a slope as shown in Figure 9 - Edexcel - GCSE Physics Combined Science - Question 5 - 2020 - Paper 1

To find the speed of the toy car at the bottom of the slope, the student should measure the distance the car rolls down and the time taken. The distance can be measured along the slope using a ruler, while the time can be recorded using a stopwatch. The speed can then be calculated using the formula:

$ext{Speed} = \frac{\text{Distance}}{\text{Time}}$

A more precise method could involve using a light gate to measure the time it takes for the car to pass through a known point.

The student must measure:

1. The vertical height of the slope (which will help determine the potential energy).
2. The mass of the toy car (to calculate kinetic energy).

The student could calculate the energy transferred to the surroundings by determining the difference between the original gravitational potential energy (GPE) at the top of the slope and the kinetic energy (KE) of the toy car at the bottom. This can be expressed mathematically as:

$\text{Energy transferred} = \text{Original GPE} - \text{KE at bottom}$

One way to reduce thermal energy transfer is to lubricate the wheels of the toy car, which will minimize friction. This reduction in friction leads to less energy being converted into thermal energy and allows more of the gravitational potential energy to be converted into kinetic energy.