Inclined Plane Friction
1. **Problem statement:** Given the coefficient of static friction $\mu = \sqrt{3}$ between a body and an inclined rough plane, find the angle of inclination $\theta$ at which the body is about to slide due to its weight alone.
2. **Understanding the physics:** The body is on the verge of sliding when the component of gravitational force down the slope equals the maximum static friction force.
3. **For an inclined plane:**
- The component of weight down the slope is $mg \sin \theta$.
- The normal force is $mg \cos \theta$.
- The maximum static friction force is $f_s = \mu mg \cos \theta$.
4. **At the point of impending motion:**
$$mg \sin \theta = \mu mg \cos \theta$$
5. **Simplify by canceling $mg$:**
$$\sin \theta = \mu \cos \theta$$
6. **Divide both sides by $\cos \theta$:**
$$\tan \theta = \mu$$
7. **Substitute $\mu = \sqrt{3}$:**
$$\tan \theta = \sqrt{3}$$
8. **Find $\theta$:**
$$\theta = \tan^{-1}(\sqrt{3}) = 60^\circ$$
**Final answer:** The inclination angle is $60^\circ$.
Hence, the correct option is (c) 60°.