No velocity will not be changed
Why?
According to Newtons 1st law the velocity of a moving object remains unchanged unless a external force affect that.
Answer:
The correct option is;
Still constant
Explanation:
The relative refractive index ₁n₂ between the two medium can be as follows;

Therefore, given that the speed of light in medium 1 is constant and the speed of light on medium 2 is also constant, the relative refractive index ₁n₂ = c₁/c₂ is always constant.
Answer: gravitational potential energy is converted into kinetic energy
Explanation:
When the diver stands on the platform, at 20 m above the surface of the water, he has some gravitational potential energy, which is given by

where m is the man's mass, g is the gravitational acceleration and h is the height above the water. As he jumps, the gravitational potential energy starts decreasing, because its height h above the water decreases, and he acquires kinetic energy, which is given by

where v is the speed of the diver, which is increasing. When he touches the water, all the initial gravitational potential energy has been converted into kinetic energy.
Answer:
50 Hz is the answer because 60 m/s divided by 1.2 meters is 50.
Hope that helps you!!! Please give me Brainliest!!!!