A ray of light traveling from air into crown glass (n = 1.52) strikes the surface at an angle of 45 degrees. What will the angle of refraction be?

R = 28 degree

Explanation:

The given parameters are:

Refractive index n = 1.52

Incident angle I = 45 degree

According to Snell law,

Sin I/Sin R = n

Where

I = angle of incidence

R = angle of refraction

n = refractive index

Substitute all the parameters into the formula

1.52 = sin 45/ sin R

Make sinR the subject of formula

Sin R = sin 45/1.52

Sin R = 0.46520

R = sin^-1(0.46520)

R = 27.72 degree

Therefore, the angle of refraction will be 28 degrees approximately.

given data:

determine the horse power (h.p) = ?

force applied to move the box(f) = 10 pounds,

box lifted from a distance         (d) = 3 feet

time taken to lift                         (t) = 10 sec,

the horse power is defined as amount of work required to move a load. the horse power is equal to 550 foot-pound per second

                  1 h.p   = 550 foot-pound/second

it can also be defined as the the load that need to be move a body for certain distance in a certain amount of time.

mathematically,

                      h.p = (force × distance)/ time

                            = (10 × 3)/ 10

                            = 30/10

                            = 3 foot -pound/sec

hence, the horse power is needed to move the box is 3 foot-pound/second

important note: 1 h.p = 550 foot-pound/second = 746 watts