# physics

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a car moving at 22.0 m/s strikes a large tree and comes to rest in a distance of 1.55m. assuming negative acceleration. what is the time needed to stop the car? what is the average acceleration

• physics -

a=v²/2s=22²/2•1.55 =156.13 m/s²
t=v/a=22/156.13=0.14 s

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