Two balls of equal mass and of perfectly elastic material are lying on the floor. One of the balls with velocity ‘v’ is made to strike the second ball. Both the balls after impact will move with a velocity

The resultant of two equal forces P making an angle $$\theta ,$$ is given by

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 framed structure is perfect, if the number of members are __________ (2j - 3), where j is the number of joints.

A. Equal to

B. Less than

C. Greater than

D. None of these

If a number of forces are acting at a point, their resultant is given by

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

The linear acceleration (a) of a body rotating along a circular path of radius (r) with an angular acceleration of $$\alpha $$ rad/s², is

A. $${\text{a}} = \frac{\alpha }{{\text{r}}}$$

B. $${\text{a}} = \alpha {\text{r}}$$

C. $${\text{a}} = \frac{{\text{r}}}{\alpha }$$

D. None of these