Question

a bus and a car,both moving with kinetic energy 10000J are retarded by applying breaks so that now both are moving with kinetic energy of 5000J .If the distance travelled by both the bus and car is 50m during this change in kinetic energy,then find the ratio of the retarding forces acting on them
please give the solution step wise step​

Answer 1

Explanation:

Retardation =2ms

−2

Time =5s

So, decrease in velocity = retardation × time =(2×5)ms

−1

=10ms

−1

Initial velocity =20ms

−1

So, final velocity = (initial velocity) − (decrease in velocity) =(20−10)ms

−1

=10ms

−1

Answer 2

Explanation:

Retarding force on bus = Kinetic energy /distance travelled by bus

Force = 10000/50 =200 N

Similarly for the car 5000/50 = 100 N.

now the ratio bus/car = 200/100 = 2/1 = 2.