The momentum of an object of mass 'm' moving with a velocity 'v' is given by:

The correct answer is mv.

Key Points

• Momentum:
  • The momentum, p of an object is defined as the product of its mass, m, and velocity, V.
  • Momentum = Mass x Velocity
  • That is, p = mv. Hence, Option 3 is correct.
  • Momentum has both direction and magnitude. Its direction is the same as that of velocity, V.
  • The SI unit of momentum is a kilogram-meter per second (kg.m.s^-1 ).
  • Newton’s second law of motion states that the time rate of change of momentum is equal to the force acting on the particle.

Important Points

• Conservation of momentum
  • It is the general law of physics according to which the quantity called momentum that characterizes motion never changes in an isolated collection of objects; that is, the total momentum of a system remains constant.
  • We can use conservation of momentum to find the change in momentum and using the impulse-momentum equation, we find the force that the block applies to the bullet.
  • Some examples of the law of conversation of momentum:
    • Air-filled balloons
    • System of gun
    • bullet Motion of rockets​

Additional Information

• The kinetic energy of an object is the energy that it possesses due to its motion.
• It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity. 
• Kinetic energy = 1/2 mv2
• The SI unit of kinetic energy is Joule or kg.m².s ^-2