A body of weight 'W' is required to move up on rough inclined plane whose angle of inclination with the horizontal is 'α'. The effort applied parallel to the plane is given by (where μ = tanφ = Coefficient of friction between the plane and the body.)

A. $$2{\text{P}}\sin \frac{\theta }{2}$$ B. $$2{\text{P}}\cos \frac{\theta }{2}$$ C. $$2{\text{P}}\tan \frac{\theta }{2}$$ D. $$2{\text{P}}\cot \frac{\theta }{2}$$

A. Equal to B. Less than C. Greater than D. None of these

A. $${\left( {\sum {\text{V}} } \right)^2} + {\left( {\sum {\text{H}} } \right)^2}$$ B. $$\sqrt {{{\left( {\sum {\text{V}} } \right)}^2} + {{\left( {\sum {\text{H}} } \right)}^2}} $$ C. $${\left( {\sum {\text{V}} } \right)^2} + {\left( {\sum {\text{H}} } \right)^2} + 2\left( {\sum {\text{V}} } \right)\left( {\sum {\text{H}} } \right)$$ D. $$\sqrt {{{\left( {\sum {\text{V}} } \right)}^2} + {{\left( {\sum {\text{H}} } \right)}^2} + 2\left( {\sum {\text{V}} } \right)\left( {\sum {\text{H}} } \right)} $$

A. $${\text{a}} = \frac{\alpha }{{\text{r}}}$$ B. $${\text{a}} = \alpha {\text{r}}$$ C. $${\text{a}} = \frac{{\text{r}}}{\alpha }$$ D. None of these