Question

The driver of a one ton car traveling at 126 km/hr suddenly used his brake to stop before
hitting a stationary lorry ahead. After the brakes are applied, a constant kinetic friction
force of magnitude 8 kilo Newton acts on the car. Ignore air resistance. (a) At what
minimum distance should the brakes be applied to avoid a collision with the other
vehicle? (b) If the distance between the vehicles is initially only 30.0 m, at what speed
would the collision occur?

Answer 1