Answer:
None of the stars give of light that is red-shifted
Explanation:
Motion of the observer or the source will cause a change in the wavelength of a wave. This is known as the Doppler effect. When an object and observer are getting close, blue shift occurs i.e., the wavelength gets shorter. When an object and observer are getting farther red shift occurs i.e., the wavelength gets longer.
Here, both the stars are getting closer to us so blue shift will occur.
It depends on the angle of the earth, and our point of view. A full moon would occur if we were to be right in front of it.
Explanation:
a)
Sum of moments = 0 (Equilibrium)
T . cos (Q)*L = m*g*L/2



b) If the String is shorter the Q increases; hence, Cos Q decreases which in turn increases Tension in the string due to inverse relationship!
c)

the answer to the question is (D)
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