posted by julia .
A string is hanging from the rearview mirror of you car and a ball is at the end of this string. Suppose that you drive around a circular track at fixed speed. Which list below gives all the forces that act on the ball?
A) tension and the force of gravity
b) tension force of gravity and centripetal force
c) tension force of gravity and friction
d) tension only
I think the answer if B but not sure if centripetal force would be included.
No, the answer is A)
"centripetal" refers to the acceleration needed to keep it in a circular path. The force need for that acceleration is provided by a component of the string tension.