Acceleration = force / mass = 20 / 2 = 10 m/s^2
Answer
given,
wavelength (λ)= 500 n m
thickness of film= 10⁻⁴ cm
refractive index = μ = 1.375
distance traveled is double which is equal to 2 x 10⁻⁴ cm
a) Number of wave


N = 2.91
N = 3
b) phase difference is equal to
Reflection from the first surface has a 180° (½λ) phase change.
There is no phase change for the 2nd surface reflection and there is no phase difference for the 2nd wave having traveled an exact whole number of waves.
net phase difference = 
= 270°
It uses electromagnetic radiation waves to enable military communications, navigation, radar, nonintrusive inspection of aircraft, and other equipment. Hope this helps.
The velocity increased from 4 m/s to 22 m/s in 3 seconds. 18 m/s in 3 seconds so the average acceleration is change in velocity divided by time. 18 m/s divided by 3 seconds = 6 m/s^2
The total mechanical energy of the ball is the sum of its potential energy U and its kinetic energy K, therefore:

so, the total mechanical energy of the basketball is 118 J.