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Find the average frictional force needed...

Find the average frictional force needed to stop a a car weighing 500 kg in a distance of 25 m (the initial speed is 72 km/h.)

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The correct Answer is:
D
`,m=500g,S=25m,u=72km/h=20m/sec,v=0`

`rarr a=((v^2-u^2))/(2S)`
`(-a)=400/50=8m/sec^2`
FrictioN/Al Force `f=ma=500xx8=4000N`
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HC VERMA-WORK AND ENERGY-Exercises
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  2. A block of weight 100 N is slowly slide up on a smooth incline of incl...

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  3. Find the average frictional force needed to stop a a car weighing 500 ...

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

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

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

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

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