Question

Which statement is true for an elastic collision in two dimensions?

Answer 1

Answer:

Kinetic energy and momentum are conserved this statement is true for an elastic collision in two dimensions.

d is correct

Explanation:

Elastic collision :

Elastic collision in two dimensions follows same rules as a collision in one dimension.

In elastic collision, The kinetic energy and momentum are same before and after collision it means momentum and kinetic energy are conserved.

Momentum is conserved :

Before collision and after collision

$m_{1}u_{1}+m_{2}u_{2}=m_{1}v_{1}+m_{2}v_{2}$

Kinetic energy is conserved:

Before collision and after collision

$\dfrac{1}{2}m_{1}u_{1}^{2}+\dfrac{1}{2}m_{2}u_{2}^{2}=\dfrac{1}{2}m_{2}v_{1}^{2}+\dfrac{1}{2}m_{2}v_{2}^{2}$

In inelastic collision :

In inelastic collision, The momentum is conserved but energy not conserved.

Hence, Kinetic energy and momentum are conserved this statement is true for an elastic collision in two dimensions.

Answer 2

Both quantities are conserved in elastic collisions. In inelastic collisions, KE is lost to deformation energy. Last answer is right