Answer:
Apply Newton's second law in the moving direction.
Explanation:
Friction force applies in the opposite direction of motion; as a restriction.
Answer:
Option B, Some of the cars' kinetic energy was converted to sound and heat energy.
Explanation:
In an elastic collision, no energy is lost during and after collision. Thus, it can be said that in an elastic collision both momentum and kinetic energy remains conserved.
While in non-elastic collision, kinetic energy of the system is lost. However, the momentum of the system is conserved. Generally, during and after collision some of the kinetic energy is lost as thermal energy, sound energy etc.
Hence, option B is correct
Answer:
The speed stays constant after the force stops pushing.
Explanation:
Speed always stays constant when the force stops pushing it.
