Gravity increased the downward speed (or decreases the upward speed) by 9.8 m/s every second.
21.2/9.8 = 2.2 seconds
I believe this is known as wave period.
hope this helps!
<span> changing its shape
changing its mass
or changing its volume</span>
Answer
given,
angle between two polarizing filters = 45°
filter reduce intensity = ?
a) I = I₀ Cos² θ
here θ = 45⁰
intensity of the light is reduced by 0.500
correct answer from the given option D
b) direction of the polarization
θ = 45°