JEE Main & Advanced
Physics
NLM, Friction, Circular Motion
Question Bank
Self Evaluation Test - Laws of Motion
question_answer
A body starts from rest on a long inclined plane of slope\[45{}^\circ \]. The coefficient of friction between the body and the plane varies as\[u=0.3\text{ }x\], where \[x\]is distance travelled down the plane. The body will have maximum speed (For\[g=10\text{ }m/{{s}^{2}}\]) when \[x=\]
A)9.8 m
B)27 m
C)12 m
D)3.33 m
Correct Answer:
D
Solution :
[d] When the body has maximum speed then \[\mu =0.3x=tan45{}^\circ ~~~~\therefore x=3.33\,\,m\]