On a ladder resting on a rough ground and leaning against a smooth vertical wall, the force of friction acts

A. $${\text{T}} = \frac{{2\omega }}{{{\pi ^2}}}$$ B. $${\text{T}} = \frac{{2\pi }}{\omega }$$ C. $${\text{T}} = \frac{2}{\omega }$$ D. $${\text{T}} = \frac{\pi }{{2\omega }}$$

A. 0.1 rad/sec B. 1 rad/sec C. 10 rad/sec D. 100 rad/sec

A. Always directed away from the centre, the point of reference B. Proportional to the square of the distance from the point of reference C. Proportional to the distance from the point of reference and directed towards it D. Inversely proportion to the distance from the point of reference

A. $${{\text{P}}^2} + {{\text{Q}}^2} + 2{\text{P}}\sin \theta $$ B. $${{\text{P}}^2} + {{\text{Q}}^2} + 2{\text{PQ}}\cos \theta $$ C. $${{\text{P}}^2} + {{\text{Q}}^2} + 2{\text{PQ}}\tan \theta $$ D. $$\sqrt {{{\text{P}}^2} + {{\text{Q}}^2} + 2{\text{PQ}}\cos \theta } $$ E. $$\sqrt {{{\text{P}}^2} + {{\text{Q}}^2} + 2{\text{PQ}}\sin \theta } $$