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Find the average frictional force needed...

Find the average frictional force needed to stop a acar wieghing 500 kg in a distance of 25 m i the initial speed is 72 km/h.

Text Solution

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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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