A car makes a horizontal circular path of radius 50 m at a constant speed of 15 m/s. What is the centripetal acceleration?

A car makes a horizontal circular path of radius 50 m at a constant speed of 15 m/s. What is the centripetal acceleration?

• A. 2.0 m/s^2
• B. 9.0 m/s^2
• C. 4.5 m/s^2
• D. 0.9 m/s^2

Answer: (C)

Centripetal acceleration is the inward acceleration needed to keep an object moving in a circle, given by a_c = v^2 / r. With speed v = 15 m/s and radius r = 50 m, a_c = (15)^2 / 50 = 225 / 50 = 4.5 m/s^2 toward the center. Since the speed is constant, there is no tangential acceleration, so the whole acceleration is centripetal.

Centripetal acceleration is the inward acceleration needed to keep an object moving in a circle, given by a_c = v^2 / r. With speed v = 15 m/s and radius r = 50 m, a_c = (15)^2 / 50 = 225 / 50 = 4.5 m/s^2 toward the center. Since the speed is constant, there is no tangential acceleration, so the whole acceleration is centripetal.