For lifting a load of 50 kg through a distance of 2.5 cm, an effort of 12.5 kg is moved through a distance of 40 cm. The efficiency of the lifting machine, is

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. $$\sqrt {{{\text{P}}^2} + {{\text{Q}}^2} + 2{\text{PQ}}\sin \theta } $$