Question

10. Suppose a car of mass 3000kg was moving at a uniform velocity of 20 km/hr. What is the work to be done by its engine to increase its velocity to 38 km/hr. ​

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.

v=60km/hr=16.66m/s

So, magnitude of work that needs to be done =

2

1

×m×v

2

Hence, work required to stop the car =

2

1

×1500×16.66

2

=208166.7J=208.17kJ

Answer 2

Explanation:

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

K.E =

2

1

× m× v

2