Answer:

Explanation:
Given that,
Radius, r = 2 m
Velocity, v = 1 m/s
We need to find the magnitude of the centripetal acceleration. The formula for the centripetal acceleration is given by :

So, the magnitude of centripetal acceleration is
.
True, They contain old stars and posses little gas or dust
Answer:
option C
Explanation:
given,
force act on west = 20 lb
force act at 45° east of north = 80 lb
magnitude of force = ?
∑ F y = 80 cos 45⁰
F y = 56.57 lb
magnitude of forces in x- direction
∑ F x = -20 + 80 sin 45⁰
= 36.57 lb
net force
F = 
F = 
F = 67.36 lb≅ 67 lb
hence, the correct answer is option C
Answer: Gravitational force between the two masses does not depend on the medium separating two masses.