A car is travelling at 10m/s when it brakes and decelerates at 2ms^-2 to a stop. How long does the car take to stop?

This is a question testing the knowledge of the equations of constant acceleration (Suvat equations)First convert the question into a standard form. For example by writing out the variables as follows s (displacement) = unknownu (initial velocity) = 10m/sv (final velocity) = 0m/sa (acceleration) = 2ms^-2t (time) = unknownYou know v, u and a and you want to calculate t, therefore the equation you need to use is v = u + a*tRe-arranging t = (v - u) / a Finally substituting in v, u and a, t = (10 - 0) / 2 = 5sSo the time taken for the car to stop is 5 seconds. 

KM

Related Physics A Level answers

All answers ▸

How does conservation of momentum work when at least one of the bodies in the problem changes mass?


What is the maximum length a bungee rope with a spring constant of 100 Nm−1 can be for an 80kg man to be able to jump from 100m above a river without touching the water?


What is a vector quantity


A light wave has a wavelength of 420nm, calculate the energy of this wave in joules.