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Question
A car of mass 2400 kg moving with a velocity of 20 m s-1 is stopped in 10 seconds on applying brakes. Calculate the retardation and the retarding force.
Solution
Let us first calculate the retardation = `((v-u))/t`
= `((0-20))/10`
= `(-20)/10`
= `(-20)/10`
= `-2 "m/s"^2`
Now, we are going to find retarding force = mass × acceleration
= 2400 kg × −2
= −4800 N
The negative sign implies that the force on the car is acting opposite to the motion of the car.
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