The power of a car engine is measured in watts, W - Edexcel - GCSE Physics - Question 3 - 2018 - Paper 1

Work done is calculated using the formula: $W = F imes d$ where:

• $W$ is the work done,
• $F$ is the force applied (1400 N), and
• $d$ is the distance moved (6.0 m).

Substituting the values: $W = 1400 ext{ N} imes 6.0 ext{ m} = 8400 ext{ J}$ Therefore, the work done is 8400 J.

The kinetic energy (KE) of an object can be calculated using the formula: $KE = \frac{1}{2} mv^2$ where:

• $m$ is the mass of the object (1200 kg), and
• $v$ is the velocity of the object (20 m/s).

Substituting the values: $KE = \frac{1}{2} \times 1200 ext{ kg} \times (20 ext{ m/s})^2$ $KE = \frac{1}{2} \times 1200 \times 400 = 240000 ext{ J}$ Thus, the kinetic energy of the car is 240000 J.