The driver of a moving car applied the brakes - Junior Cycle Science - Question b - 2007

To calculate the work done, we use the formula:

$W = F imes d$

where:

• $W$ = work done (in joules)
• $F$ = force applied (in newtons)
• $d$ = distance moved in the direction of the force (in meters)

Given:

• $F = 8000 \, N$
• $d = 20 \, m$

Substituting the values:

$W = 8000 \, N \times 20 \, m = 160000 \, J$

Thus, the work done in stopping the car is $160000 \, J$ or $160 \, kJ$.