Answer:
22 degree
Explanation:
Angle of incidence, i = 30 degree
the refractive index of water with respect to air is 4/3.
As the ray of light travels from rarer medium to denser medium, that mean air to water, the refraction takes place.
According to Snell's law,
Refractive index of water with respect to air = Sin i / Sin r
Where, r be the angle of refraction
4 / 3 = Sin 30 / Sin r
0.75 = 2 Sin r
Sin r = 0.375
r = 22 degree
Thus, the angle of refraction is 22 degree.
The elastic potential energy of a spring is given by

where k is the spring's constant and x is the displacement with respect to the relaxed position of the spring.
The work done by the spring is the negative of the potential energy difference between the final and initial condition of the spring:

In our problem, initially the spring is uncompressed, so

. Therefore, the work done by the spring when it is compressed until

is

And this value is actually negative, because the box is responsible for the spring's compression, so the work is done by the box.
Answer:

Explanation:
Given


Required
Determine the speed of the jet
The speed is calculated as:

Substitute 4800 km for Distance and 6hr for Time


<em>Hence, the speed of the commercial jet is 800km/hr</em>
The best way to deterime which cloth with absorb heat is to put each cloth outside in the heat with a thermometer under it and see which has the highest tempe.