Question

A 2000kg car starts to coast up the hill. It's speed is 20ms-1 at A. If it's speed is 5ms-1 at B, how an average frictional force related it's motion? The distance along the road is 40m.. ​

Answer 1

Answer:

Here, two balls each of mass 0.25 kg are moving towards each other than in a straight line, one at 3ms

−1

and the other at 1ms

−1

collide and the balls stick together after the collision, hence

m

1

u

1

−m

2

u

2

=(m

1

+m

2

)v

(0.25)(3)−(0.25)(1)=(0.25+0.25)v

(0.75)−(0.25)=(0.5)v

v=1ms

−1

please mark mein brain list at least I have answered something