Answer the following question given this paragraph: 

Figure 6.11 The frictional force supplies the centripetal force and is numerically equal to it. Centripetal force is perpendicular to velocity and causes uniform circular motion. The larger the F c , the smaller the radius of curvature r and the sharper the curve. The second curve has the same v , but a larger.


Q: What force is perpendicular to velocity and causes uniform circular motion?

 Choices:

- centripetal torque

- circular friction

- tangential force

- centripetal force

A:
centripetal force
