Why is 30% recommended as the minimum michelson contrast?

Explained

Explanation:

Michelson contrast is used for patterns where the distribution of bright and dark segments is nearly equal.

It is given by:

where I_max = maximum illumination and I_min = minimum illumination

we know that

typically, I_min = 54% of I_max  (general standard)

or I_min = 0.54 I_max

putting this value in above equation to get m

this approximately corresponds to m = 0.3 or 30%

hence, 30% recommended as the minimum Michelson contrast

answer: d. a cme increases the amount of energy in the solar wind

explanation:

coronal mass ejections, also called cmes, are large clouds of plasma and magnetic field that erupt from the sun. only when the cloud is aimed at earth will the cme hit earth and therefore cause impacts. high-speed solar wind streams come from areas on the sun known as coronal holes.