State and prove the principle of conversation of linear momentum. Apply this law, to explain why the boat moves away, when a man jumps from it to the shore.

State and explain the law of conservation of linear momentum. Explain recoil of a gun and explosion of a bomb.

A man is moving away from a tower 41.6 m high at the rate of 2 m/sec. Find the rate at which the angle of elevation of the top of tower is changing, when he is at a distance of 30m from the foot of the tower. Assume that the eye level of the man is 1.6m from the ground.

State the principle,which helps us to determine the shape of the wavefront at a later time from its given shape at any time.Apply this principle to Derive Snell's law of refraction by drwing the refracted wavefront corresponing to a plane wavefront incident on the boundary separating a rarer medium from a denser medium.

According to the third law of motion when we push on an object, the object pushes back on us with an equal and opposite force. If the object is a massive truck parked along the roadside, it will probably not move. A student justifies this by answering that the two opposite and equal forces cancel each other. Comment on this logic and explain why the truck does not move.