FrictionHard
Question
Starting from rest a body slides down a 45o inclined plane in twice the time it takes to slide down the same distance in the absence of friction. The co-efficient of friction between the body and the inclined plane is:
Options
A.0.75
B.0.33
C.0.25
D.0.80
Solution
Let acceleration in Ist case is a1 and that in second case is a2
Now
a1t2 = 
a2(2t)2 ⇒ a2 = 
............(i)Clearly a1 =
= g sin θ − μg cos θ ............(ii) and a2 =
= g sinθ − mg cosθ ............(iii)From (i), (ii) and (iii),
we get μ = 0.75.
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