Answer:
51.94°
Explanation:
= Unpolarized light
= Light after passing though second filter = 
Polarized light passing through first filter

Polarized light passing through second filter

The angle between the two filters is 51.94°
Answer:
Only main sequence stars have a well-defined relationship between spectral type and luminosity.
Explanation:
Low-mass stars have much longer lifetimes than high-mass stars.
Answer:
e. 1.2 x 10²³
Explanation:
According to the problem, The current equation is given by:

Here time is in seconds.
Consider at t=0 s the current starts to flow due to battery and the current stops when the time t tends to infinite.
The relation between current and number of charge carriers is:

Here the limits of integration is from 0 to infinite. So,


q = 1.90 x 10⁴ C
Consider N be the total number of charge carriers. So,
q = N e
Here e is electronic charge and its value is 1.69 x 10⁻¹⁹ C.
N = q/e
Substitute the suitable values in the above equation.

N = 1.2 x 10²³
5.08
hope you got it right !
They are slowed down.
even air is a medium and will slow down waves (slightly) compared to a vacuum/ space
if the wave hits the medium at an angle it can be 'bent' (refracted) like light through a glass prism