Question

Question #2d4b3

Answer 1

The kinetic energy will be halved.

Explanation:

Kinetic energy is given by:

`E_k=1/2*m*v^2`

It is proportional to the object's mass:

`Epropm`

If we double the mass, we double the energy:

`E_1=1/2*1*v^2=1/2v^2`

`E_2=1/2*2*v^2=1v^2=color(blue)(2E_1)`

Kinetic energy is also proportional to the square of the velocity:

`Epropv^2`

This means that if we halve the velocity, we quarter the energy:

`E_1=1/2*m*1^2=1/2*m`

`E_2=1/2*m*(1/2)^2=1/2*m*(1/4)=1/8*m=color(blue)(1/4*E_1)`

If we combine a doubled mass and halved velocity, our initial energy will be doubled and then quartered. This results in an overall halving of the energy:

`E_2=E_1*2*1/4=1/2E_1`