Answer:
11.3 m/s
Explanation:
KE₁ = KE₂
½m₁v₁² = ½m₂v₂²
½ (2 kg) v² = ½ (4 kg) (8 m/s)²
v ≈ 11.3 m/s
Force=mass x acceleration
f= 0.5 x40
f=20N
The basic difference is that the ordinary sources are incoherent that means that the discrete frequencies merge up to give an intermediate between the maximum and minimum frequencies. While the laser is coherent containing the single frequency with maximum amplitude. thus travelling far.