A stationary body of mass m explodes into 3 parts of masses m in the ratio 1 : 3 : 3, its two fractions having equal masses moving at right angles to each other with a velocity of 15 $ms^{-1}$ . What is the velocity of the third body

Applying law of conservation of momentum, we get $\sqrt{2} \, p = p_3$ i.e. $\sqrt{2} \times 3m \times 15 = m \times \upsilon$ i.e. $\upsilon = 45\sqrt{2} \, m\, s^{-1}$

A stationary body of mass m explodes into 3 parts

Notes on laws of motion

Concepts Used:

Laws of Motion

The laws of motion, which are the keystone of classical mechanics, are three statements that defined the relationships between the forces acting on a body and its motion. They were first disclosed by English physicist and mathematician Isaac Newton.

Newton’s First Law of Motion

Newton’s 1^st law states that a body at rest or uniform motion will continue to be at rest or uniform motion until and unless a net external force acts on it.

Newton’s Second Law of Motion

Newton's 2^nd law of motion deals with the relation between force and acceleration. According to the second law of motion, the acceleration of an object as built by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object.

Newton’s Third Law of Motion

Newton's 3^rd law of motion states when a body applies a force on another body that there is an equal and opposite reaction for every action.

A stationary body of mass m explodes into 3 parts of masses m in the ratio 1 : 3 : 3, its two fractions having equal masses moving at right angles to each other with a velocity of 15 $ms^{-1}$. What is the velocity of the third body

The Correct Option is D

Solution and Explanation

Top Questions on laws of motion