A car of mass m travelling with a velocity v comes to rest over a distance d in time t. The constant frictional force acting on the car while it is braking is found using:
Newton's Second Law: F=maa=v-u/tUsing SUVAT equations: v2= u2+2asv (final velocity)=0 u(inital velocity)= v s=d Rearranging gives: -v2=2ad a=-v2/2d Therefore F= -mv2/2dNegative sign suggests the car is slowing down (negative acceleration)
GH
Related Physics A Level answers
All answers ▸What velocity should your boat have if you want to cross a 72m wide river in 6s by the shortest distance, with a 5 m/s downstream current?
What is the total capacitance of a circuit containing a 3microfarad capacitor and a 2microfarad capacitor in series.
Why do gravitational fields around point masses obey an inverse square law?
In still air an aircraft flies at 200 m/s . The aircraft is heading due north in still air when it flies into a steady wind of 50 m/s blowing from the west. Calculate the magnitude and direction of the resultant velocity?