Grade 9Mechanics

a car of mass 1000 kg rests on a horizontal road initially.it is then pushed over 5 m to a speed of 1 m/s before the engine is started .if the average frictional force acting on the car is 500 newtons the total work done in moving the car before the driver starts the engine is started

sumanth

10 Years agoGrade 9

2 Answers

ram charan

10 Years ago

v=u+at

1=at

s=ut+1/2at^2

u=0m/s

s=1/2at^2

at=1m/s

5m=t/2

t=10s

a=0.1m/s^2

w=mas-500*0.1

1000*0.1*5 – 50J

work done =+450J

Bandana

7 Years ago

Case 1

The car is pushed to a speed of 1m/s over a distance of 5m.

So, the car is accelerated.

KE = ½ × m × v^2

= ½ × 1000 × 1^2

= 500 J

Work done against friction = Fs

= 500 × 5

= 2500 J

Total work done = 2500 + 500

= 3000 J

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a car of mass 1000 kg rests on a horizontal road initially.it is then pushed over 5 m to a speed of 1 m/s before the engine is started .if the average frictional force acting on the car is 500 newtons the total work done in moving the car before the driver starts the engine is started

sumanth

2 Answers

ram charan

Bandana

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