A motorcycle and its rider have a total mass of 240 kg. During a test on a horizontal track, the brakes exert a constant force of 1200 N until the motorcycle stops.
A stronger braking system is considered for the motorcycle.
Explain why increasing the braking force would reduce the distance needed to stop from the same speed.
A technician's report states that the motorcycle, braking from 15 m/s, comes to rest in a braking distance of 22.5 m.
Show that this braking distance is consistent with the motorcycle's initial kinetic energy.
For another test, the motorcycle begins braking at a speed that is 20% greater than 15 m/s. The braking force remains 1200 N.
Calculate the braking distance in this test.
Two tests use the same motorcycle and braking force. In the first test, the motorcycle brakes from 10 m/s; in the second, it brakes from 14 m/s. A technician concludes that the second test's braking distance is 40% greater.
Explain why this conclusion is incorrect.
126 exam-style questions on Edexcel GCSE Physics 2.5 Stopping and braking distances, covering 2.5.1 Stopping distance and reaction time, 2.5.2 Factors affecting stopping distance, 2.5.3 Dangers of large decelerations, and 2.5.4 Braking distance and initial speed. Each one has a worked solution and a mark scheme showing where the marks go.