Thank you for the message my friend, yoU have a good day as well :)
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.
It’s solved by using a pretty standard formula for efficiency.
Answer:
Explanation:
Suppose v is the initial velocity and 
is the angle of inclination
distance traveled in vertical direction in t=1 s
When gravity is present
where 
here initial velocity is v\sin \theta [/tex] so
In absence of gravity
Answer:
The pull or push which changes or tends to change the position of an object from rest to motion or motion to rest is known as force.
Its SI unit is newton(n).
