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3 years ago

At which angle must a laser beam enter the water for no refraction to occur?

1 answer:

5 0

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.

You might be interested in

If an object is propelled upward from a height of 128 feet at an initial velocity of 112 feet per second, then its height h aft

Marina CMI [18]

Explanation:

The equation of motion of an object is given by :

$h(t)=-16t^2+112t+128$

Where

t is the time in seconds

We need to find the time when the object hits the ground. When the object hits the ground, h(t) = 0

So,

$-16t^2+112t+128=0$

$-t^2+7t+8=0$

On solving above equation using online calculator, t = 8 seconds. So, the object hit the ground after 8 seconds. Hence, this is the required solution.

8 0

3 years ago

How much does the Earth weigh? Why does the moon appear in the daytime?

ch4aika [34]

Answer:

moon disappear because of the rotation

7 0

3 years ago

A tennis player swings and hits the ball away. How does the force of the tennis racket affect the motion of the ball

defon

The force of the racket affects the ball's motion because it changes the momentum of the ball.

<h3>Impulse received by the ball</h3>

The impulse received by the ball through the racket affects the motion because it changes the momentum of the ball.

The ball which is initially at rest, will gain momentum after been hit with the racket.

J = ΔP = Ft

where;

J is the impulse received by the ball
ΔP is change in momentum of the ball
F is the applied force
t is the time of action

Thus, the force of the racket affects the ball's motion because it changes the momentum of the ball.

Learn more about impulse here: brainly.com/question/25700778

4 0

2 years ago

What is the angular displacement of a minute hand of a clock after 3 minutes?

Inessa [10]

Answer:

π/10 rads

Explanation:

It takes an hour (60 minutes) for the minute's hand to turn a full circle or achieve an angular rotation of

2πl rad.

Now, number of periods of 3 minutes in an hour is;

Number of periods = 60/3 = 20 periods

Thus, 3 minutes rotation accounts for 1/20 of 2π the rotation of the minute's hand in an hour.

Thus;

Angular displacement = (1/20) * 2π = π/10 rads

6 0

2 years ago

On your first day at work as an electrical technician, you are asked to determine the resistance per meter of a long piece of wi

Lostsunrise [7]

Answer:

$0.06\Omega/m$

Explanation:

Firstly, when you measure the voltage across the battery, you get the emf,

E = 13.0 V

In order to proceed we have to assume that the voltmeter offers no loading effect, which is a valid assumption since it has a very high resistance.

Secondly, the wires must be uniform. So the resistance per unit length is constant (say z). Now, even though the ammeter has very little resistance it cannot be ignored as it must be of comparable value/magnitude when compared to the wires. This is can seen in the two cases when currents were measured. Following Ohm's law and the resistance of a length of wire being proportional to it's length, we should have gotten half the current when measuring with the 40 m wire with respect to the 20 m wire ( $I=\frac{V}{R}$ ). But this is not the case.