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 ▸

What are Newton's 3 laws of motion?


Describe how standing waves are formed and explain why nodes and antinodes are formed.


A ball is initially at rest and is dropped from a height of 10m. Calculate the velocity of the ball when it reaches the ground


An atom can become excited by the absorption of photons. Explain why only photons of certain frequencies cause excitation in a particular atom.