Question
A plank with a box on it at one end is gradually raised about the other end. As the angle of inclination with the horizontal reaches 30o, the box starts to slip and slides 4.0 m down the plank in 4.0 s. The coefficients of static and kinetic friction between the box and the plank will be respectively
-
0.6 and 0.6
-
06 and 0.5
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0.5 and 0.6
-
0.4 and 0.3
Solution
B.
06 and 0.5
Given a plank with a box on it one end is gradually raised about the end having angle of inclination is 300, the box starts to slip and slides down 4 m the plank in 4 s as shown in a figure.
The coefficient of static friction.
So, distance covered by a plank,
Thus, coefficient of kinetic friction between the box and the plank is 0.51
