A car travelling at 28 m/s brakes until it stops completely after travelling a distance of 15 m. Calculate the deceleration of the car.
· Firstly, we need to note down what we have: distance travelled, s =15 m; initial velocity, u = 28 ms-1; final velocity, v = 0 because the car comes to rest; we are looking for the deceleration hence a; since we are using s, u, v and a, we need to use the "suvat" equation that contains those four letters ----- v2 = u2 + 2as· By rearranging the equation ---- a = (v2 - u2) / 2s = -282 / (2 x 15) = -784/30 = -26 ms-2 (the minus sign is because deceleration is a decrease in speed rather than an increase)
OS
Related Physics A Level answers
All answers ▸A boy (25kg) and a girl (20kg) are playing on a see-saw which is 4m long. If the boy sits 1m from the centre on the left side and the girl 2m from the centre on the other, which direction will the see-saw will rotate around its centre?
A child is going down a snowy hill on a sledge. Draw a free-body force diagram for the child and sledge.
People A and B are taking a lift of mass 500 kg which has constant acceleration and the force from the rope that pulls it is 7500 N. The scales where the people stand show a reading of 720 N and 500 N.
When catching a ball, a cricketer moves his hands for a short distance in the direction of travel of the ball as it makes contact with his hands. Explain why this technique results in less force being exerted on the cricketer's hands