(1) What is the centripetal acceleration of the solar system toward the galactic center?
The goal is to be able to use the equation .
The value for r was given in the problem, so it remains to find v. Velocity has dimensions of distance over time. The time to complete one orbit was given, so if the distance of one complete orbit is found, the value for v will follow. The distance of one orbit is the circumference of the circle with a radius of . Therefore, velocity is found as