Physics

Problem

A given object takes

n

times the time to slide down

45^\circ

rough inclined plane as it takes the time to slide down an identical perfectly smooth

45^\circ

inclined plane. The coefficient of kinetic friction between the object and the surface of inclined plane is : (1)

1 - \frac{1}{n^2}

(2)

1 - n^2

(3)

\sqrt{1 - \frac{1}{n^2}}

(4)

\sqrt{1 - n^2}