An insect crawls up a hemispherical surface very slowly (see the figure). The coefficient of friction between the insect and the surface is 1/3. If the line joining the centre of the hemispherical surface to the insect makes an angle \[\alpha \]with the vertical, the maximum possible value of \[\alpha \] is given by [IIT-JEE 2001]

If assertion is true but reason is false.

\[\text{cosec}\,\alpha =\text{3}\]

An insect crawls up a hemispherical surface very slowly (see the figur

1.	An insect crawls up a hemispherical surface very slowly (see the figure). The coefficient of friction between the insect and the surface is 1/3. If the line joining the centre of the hemispherical surface to the insect makes an angle \[\alpha \]with the vertical, the maximum possible value of \[\alpha \] is given by [IIT-JEE 2001]
A.	\[\cot \alpha =3\]
B.	\[\tan \alpha =3\]
C.	If assertion is true but reason is false.
D.	\[\text{cosec}\,\alpha =\text{3}\]
Answer» B. \[\tan \alpha =3\]

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