The answer for this question, If I am correct, should be answer "D".
Answer:
The observer detects light of wavelength is 115 nm.
(b) is correct option
Explanation:
Given that,
Wavelength of source = 500 nm
Velocity = 0.90 c
We need to calculate the wavelength of observer
Using Doppler effect

Where, 


Hence, The observer detects light of wavelength is 115 nm.
Answer:
41 turns
Explanation:
= Induced emf = 12.4 mV
= Current changing rate = 0.0275 A/s
L= Inductance
= Average flux = 0.00285 wb
N = Number of turns
Change in flux is given by

Flux through each turn is given by

The number of turns is 41
Answer:
I think milligram is the correct answer.
The angle of reflection is the angle that the reflected ray makes with a line drawn perpendicular to the reflecting surface.