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A plank with a box on it at one end is g...

A plank with a box on it at one end is gradully raised about the other end. As the angle of inclination with the horizntal reaches `30^(@)` , the box starts to slip and slide `4.0m` down the plank in `4.0s` . The coefficients of static and knitic friction between the box and the plank will be, respectively.

A

0.6 and 0.6

B

0.6 and 0.5

C

0.5 and 0.6

D

0.4 and 0.3

Text Solution

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The correct Answer is:
B
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