because the season change if you are in summer the days seem longer because the sun stays up longer if you are in the winter the days seem shorter because the sun goes down sooner.
Diffraction grating consists of a large number of fine slits.
Light gets split into different colors due to these slits of the diffraction grating.
Thus, diffraction grating produces a pattern of the coloured bands as each light wave passes through the slit at different speeds and different angles.
Answer:
57 N
Explanation:
Draw a free body diagram. There are three forces:
Weight force mg pulling down.
Normal force N pushing up.
Friction force F pushing horizontally.
Sum of the forces in the y direction:
∑F = ma
N − mg = 0
N = mg
Friction force is the product of normal force and coefficient of friction:
F = Nμ
F = mgμ
F = (65 kg) (9.8 m/s²) (0.09)
F = 57.3 N
Rounded, the friction force is 57 N.
Once the starlight or moonlight comes down the tube and hits the big main mirror at the bottom, it's reflected, and heads back up the tube, along the same way it came in. But if you're looking through an eyepiece, the eyepiece is on the SIDE of the tube. So you need another small mirror, to catch the focused light before it goes up out of the tube, and send it sideways to the eyepiece.