Question

Find the Cartesian coordinates of B(4,25⁰,120⁰)

(a) (0.845, 1.462, 3.625)

(b) (-0.845, 1.462, 3.625)

(c) (-8.45, 2.462, 6.325)

(d) (8.45, 2.462, 6.325)

This question was addressed to me in an online interview.

My question is taken from Spherical Coordinate System topic in section Coordinate Systems and Transforms of Electromagnetic Theory

Answer 1

Correct option is (b) (-0.845, 1.462, 3.625)

To elaborate: x = r sin θ cos φ = 4 sin25⁰ cos 120⁰ = -0.845

y = r sin θ sin φ = 4 sin 25⁰ sin 120⁰ = 1.462

z = r cos θ = 4 cos 25⁰ = 3.625.