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 do I convert between eV and J


Calculate the kinetic energy of a proton moving at 95% of the speed of light. (c = 3x10^8 m/s, m_p = 1.67x10^-27 kg) [4 marks]


A 12V lamp, 36W is switched on for 1 hour. Find the energy supplied by the battery.


How are X-Rays produced?