Let $$E$$ be the ellipse $${{{x^2}} \over 9} + {{{y^2}} \over 4} = 1$$ and $$C$$ be the circle $${x^2} + {y^2} = 9$$. Let $$P$$ and $$Q$$ be the points $$(1, 2)$$ and $$(2, 1)$$ respectively. Then

The point of intersection of the tangents at the ends of the latus rectum of the parabola $${y^2} = 4x$$ is ...... .

A block of mass 0.1 is held against a wall applying a horizontal force of 5 N on the block. If the coefficient of friction between the block and the wall is 0.5, the magnitude of the frictional force acting on the block is:

A particle of mass m is moving in a circular path of constant radius r such that its centripetal acceleration $${a_c}$$ is varying with time t as $${a_c}$$ = k²rt² where k is a constant. The power delivered to the perticles by the force acting on it is: