The angular elevation of an enemy's position on a hill 'h' ft height is `alpha`.Wha should be the minimum velocity of the projectile in order to hit the enemy?

The angular elevation of an enemies position on a hill of height 'h' is alpha . Show that in order to hit a shell on it, the initial velocity 'u' of projection should not be less than sqrt((gh (1+ cosec alpha)) where g is acceleration due to gravity.

A stone of mass m is to be thrown to a height h. With what minimum velocity should it be thrown?

An airplane is moving with velocity v_0 horizontally at a height h. If a projectile is fired at the instant when the plane is overhead, What must be the angle of projection amd minimum velocity of projection in order that it may hit the airplane ?

An airplane is moving with velocity v_0 horizontally at a height h. If a projectile is fired at the instant when the plane is overhead, what must be the angle of projection and minimum velocity of projection in order that it may hit the airplane ?

Suppose the rod with the balls A and B of theprevious problem is clamped at the centre in such a way that it ca rotate freely about a horizontal axis through the clamp. The system is kept at rest in the horizontal position. A particle P of the same mass m is dropped from a heigh h hon the ball B. The particle collides with B and sticks to it. a. Find the angular momentum and the angular speed of the system just after the collision. b. What should be the minimum value of h so that the system makes a full rotation after the collision.

Suppose the rod with the balls A and B of theprevious problem is clamped at the centre in such a way that it ca rotate freely about a horizontal axis through the clamp. The system is kept at rest in the horizontal position. A particle P of the same mass m is dropped from a heigh h hon the ball B. The particle collides with B and sticks to it. a. Find the angular momentum and the angular speed of the system just after the collision. b. What should be the minimum value of h so that the system makes a full rotation after the collision.

Four small particles charged with equal positive charges Q each are arranged at the four corners of a horizontal square of side a. A unit positive charge mass m is placed at a point P, at a height h above the centre of the square. What should be the magnitude of charge Q in order that the unit charge remain in equilibrium