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Find the averasge force needed to accele...

Find the averasge force needed to accelerate a car weighing 500 kg form rest to 72 km/h in a distance of 25 m.

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The correct Answer is:
D
mk500kg, u=0, v=70 km/h=20 m/sec
`a((v^2-u^2))/(2S)`
`=400/50=8m/sec^2`

Froce needed to accelerate the car
`F=ma=500xx8=400N`
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HC VERMA-WORK AND ENERGY-Exercises
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  2. Find the average frictional force needed to stop a a car weighing 500 ...

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  3. Find the averasge force needed to accelerate a car weighing 500 kg for...

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  4. A particle of mass m moves on a straight line with its velocity varyin...

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  5. A block of mass 2.0 kg kept at rest on an inclined plane of inclinatio...

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  6. A block of mass 2.0 kg is pushed down an inclined plane of inclination...

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  7. A 250 g block slides on aeroug horizontal table. Find the work donen b...

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  8. Water falling from a 50 m high fall is to be used for generating elect...

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  12. The US athlete Florence Griffith oyner won the 100 m spring gold medal...

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  13. A water pump lifts water from a level 10 m below the ground. Water is ...

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  14. An unruly demonstrator lifts a stone of mass 200 g from the ground and...

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  15. In a factory it is desired to lift 2000 kg of metal through a distance...

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  16. Express each of the following numbers as a product of its prime factor...

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  17. A block of mass 30.0 kg is being brought down by a chain. If the block...

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  18. The heavier block in an atwood machine has a mass twice that of the li...

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  19. The two blocks in an Atwood machine have masses 2.0 kg and 3.0 kg. Fin...

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  20. Consider the situatioin shown in figure. The system is released from r...

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