Question

Is the principle of conservation of momentum violated when vehicles stop on the application of brakes?

Answer 1

Conservation of momentum:

1. The law of conservation of momentum asserts that perhaps the total momentum of two or more participants operating on one other in an isolated system stays unchanged until an external force is introduced.
2. As a result, momentum cannot be generated or destroyed.

Mathematically, this can be represented as:

${\mathrm{m}}_1{\mathrm{u}}_1+{\mathrm{m}}_2{\mathrm{u}}_2={\mathrm{m}}_1{\mathrm{v}}_1+{\mathrm{m}}_2{\mathrm{v}}_2$

m₁ is the mass of the blowing ball.

m₂ is the mass of the blowing ball.

u₁ and u₂ are the initial velocities.

v₁ and v₂ are the final velocities.

Explanation:

1. There is no external force acting on the system, this same described scenario adheres to the principle of conservation of momentum. When we apply the brake pedal to a car, it comes to a stop due to the retarding force.
2. The above happens in such a manner that the entire loss of momentum of the automobile equals the gain in momentum of the braking system, that is the change in momentum of the applied force. As a result, the system's overall momentum is preserved.

Therefore, no, it doesn’t violate the principle of conservation of momentum.