The moon is observed from two diametrically extremes A and B on earth .The angle of parallax is found to be 1°54' . If the diameter of the earth is about 1.276x10^7 m, estimate the distance of the moon from the earth.

Dear student,
We will measure the distance of the moon from the earth using parallax method.
Given Angle = ѳ = 1⁰54' = (3600x54x60)/3600  x (π/180)
Diameter of the earth = b = 1.276 x 10⁷m
Distance of the moon from the earth = s
So we know Angle = Arc/Radius

1. or ѳ = b / s

So distance s = b / ѳ
On putting values we get s = 3.85 x 10⁸m
So the distance of moon from the earth is 3.85 x 10⁸m
Regards.