KE=1/2 m v^2
KE= .5 x 2kg x 15m/s to the 2nd power
KE=225 km/s
The answer is to your question is c
Force moves the object but if the same anyone force is applied to both sides then it doesn’t move
Explanation:
We need to calculate the speed of light in each materials
(I). Gallium phosphide,
The index of refraction of Gallium phosphide is 3.50
Using formula of speed of light
....(I)
Where,
= index of refraction
c = speed of light
Put the value into the formula


(II) Carbon disulfide,
The index of refraction of Gallium phosphide is 1.63
Put the value in the equation (I)


(III). Benzene,
The index of refraction of Gallium phosphide is 1.50
Put the value in the equation (I)


Hence, This is the required solution.