Question

A car of mass 2000 Kg starting from rest accelerates at the rate of 2m/s2 through a distance of 400 m. The road offers a frictional force of 200 N. Calculate the net accelerating force acting on the car and the total force produced by the engine of the car.

Answer 1

Answer:

Mass of the car m=1000 kg

Initial velocity of car v

1

=0

Final velocity of car v

2

=100km/h=100×

18

5

m/s=27.78m/s

Average power of car=change in kinetic energy per unit time=

t

2

1

mv

2

2

−

2

1

mv

1

2

,since v

1

=0

So,average power of car=

t

2

1

mv

2

2

=

5

2

1

×1000×27.78

2

=7.71×10

4

W