Answer:
7.19 * 10^14J
Explanation:
Given that
Density of water Pwater= 1000kg/m3
R=2.1km = 2.1*10^3m
H= 2.3cm. = 2.3*10^-2m
Lv water= 2256 * 10^3J/kg
First, mass of water need to be calculated, using an imaginary cylinder
Density= Mass /Volume
Mass= Density* Volume
Volume of a cylinder= πR2h
Therefore mass= PπR2H
= 1000 * π * (2.1 *10^3)^2 * (2.3 * 10^-2)
= 3.18 *10^8
Heat Released Qv = mLV
= 3.18*10^8 * 2236*10^3
= 7.19 * 10^14J
If you could please give me a already given speed I could estimate it. since there is no speed shown you wouldn't be able to estimate the speed of the moving train.
Light that enters the new medium <em>perpendicular to the surface</em> keeps sailing straight through the new medium unrefracted (in the same direction).
Perpendicular to the surface is the "normal" to the surface. So the angle of incidence (angle between the laser and the normal) is zero, and the law of refraction (just like the law of reflection) predicts an angle of zero between the normal and the refracted (or the reflected) beam.
Moral of the story: If you want your laser to keep going in the same direction after it enters the water, or to bounce back in the same direction it came from when it hits the mirror, then shoot it <em>straight on</em> to the surface, perpendicular to it.
