How is the distance defined between two radical planes of the spheres at angles Ø and (Ø + dØ ) ?

a. r sin θ dФ

b. sin θ dФ

c. r dФ

d. r + sin θ dФ

ANSWER: r sin θ dФ

Explanation:

The locus of points which comprises similar powers corresponding to the two spheres is known as radical plane.

Therefore, the distance between two radical planes of the spheres is equal to the product of radius vector measured from Z-axis, sine angle between Z-axis & radius vector and the angle between X-axis and radius vector projection in XY plane.