Question

Calculate work required to be done to stop a car of 1500 kg moving at a velocity of 60km/h. b)A car weighing 1200 kg is uniformly accelerated from rest and covers a distance of 40m in 5s. Calculate the work done by the engine of car during this time. What is the final kinetic energy of car. ​

Answer 1

Answer:

When a object is moving with a constant velocity, it possess K.E

K.E=

2

1

×m×v

2

So, in order to bring the object to rest i.e its same magnitude of energy is required so, as the final final energy comes to zero.

So, magnitude of work that needs to be done =

2

1

×m×v

2

60km/hr=16.66m/s

So, work required to stop the car =

2

1

×1500×16.66

2

⇒=208166.7J=208.17kJ