Final answer:
The direction of b−a can be determined using the right-hand rule for the cross product of vectors. Therefore, the answer is (c) Opposite to b.
Step-by-step explanation:
The direction of b−a can be determined using the right-hand rule for the cross product of vectors. In this case, vector a represents the centripetal force and vector b represents the tangential velocity. Using the corkscrew right-hand rule, we can place a corkscrew in the direction perpendicular to the plane that contains vectors a and b, and turn it from the first to the second vector to determine the direction of b−a. Therefore, the answer is (c) Opposite to b.