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.
Answer:
The correct option is;
How loud or soft the sound is
Explanation:
The loudness of a sound wave is given by the amount of energy that the pressure wave carries and it is measured in decibels (dB) which is the relative intensity of the pressure wave of a sound to the standard pressure
A loud sound has a high amplitude and a soft sound has a low amplitude, such that as the amplitude of the sound is increased, due to increased energy input, the sound becomes louder, and as the amplitude of the sound is decreased due to reduced energy input, the sound becomes softer.
Population size is the actual number of individuals in a population. Population density is a measurement of population size per unit area, i.e., population size divided by total land area. Abundance refers to the relative representation of a species in a particular ecosystem.
<span>Mercury, Venus, Earth, and Mars are all ___inner___ planets. This is because they are all within the asteroid belt.</span>
Answer:
Mechanical energy = 3.92 J
exactly 3.92 j
Explanation:
As we know that mechanical energy is sum of kinetic energy and potential energy of the system
so here we can say that mechanical energy is sum of kinetic energy of ball and its potential energy
Since ball is at rest so kinetic energy of the ball must be ZERO
Now for potential energy we know that
now we know
m = 0.2 kg
h = 2 m
now for potential ene'rgy
so mechanical energy is given as
Mechanical Energy = 3.92 + 0 = 3.92 J
