Planet Z-34 has a mass equal to one-third that of Earth and a radius equal to one-third that of Earth.With g representing,as usual,the acceleration due to gravity at the surface of Earth,the acceleration due to gravity at the surface of Z-34 is
A)g/3.
B)3g.
C)6g.
D)g/9.
E)9g.

Question

Quizplus · Accepted Answer

The acceleration due to gravity is proportional to the mass and inversely proportional to the square of the radius. Since the mass and radius of Z-34 are both one-third that of Earth, the acceleration due to gravity at the surface of Z-34 would be (1/3)/(1/3)^2 * g = 3g. Therefore, the answer is choice B.

Planet Z-34 Has a Mass Equal to One-Third That of Earth