Question 235: Laws of Motion

Question

The upper half of an inclined plane of inclination $$	heta $$ is perfectly smooth while lower half is rough. A block starting from rest at the top of the plane will again come to rest at the bottom, if the coefficient of friction between the block and lower half of the plane is given by

Accepted Answer

For upper half of inclined plane
v
2
= u
2
+ 2a S/2 = 2 (g sin $$	heta $$) S/2 = gS sin $$	heta $$
For lower half of inclined plane
0 = u
2
+ 2 g (sin $$	heta $$ Ã¢ÂÂ $$\mu $$ cos $$	heta $$) S/2
$$ \Rightarrow  - gS\sin 	heta  = gS\left( {\sin 	heta  - \mu \cos 	heta } ight)$$
$$ \Rightarrow 2\sin 	heta  = \mu \cos 	heta $$
$$ \Rightarrow \mu  = {{2\sin 	heta } \over {\cos 	heta }} = 2	an 	heta $$

Answer

$$\mu $$ = 2 tan$$	heta $$

Answer

$$\mu $$ = tan$$	heta $$

Answer

$$\mu $$ = $${1 \over {	an 	heta }}$$

Answer

$$\mu  = {2 \over {	an 	heta }}$$

Laws of Motion

The upper half of an inclined plane of inclination $\theta $ is perfectly smooth while lower half is rough. A block starting from rest at the top of the plane will again come to rest at the bottom, if the coefficient of friction between the block and lower half of the plane is given by

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