Acceleration in Uniform Circular Motion

[sleepingarmy]

Homework Statement

What is the acceleration (in m/s^2) of a 10 kg mass moving with speed 2 m/s in uniform circular motion about a circle of radius 2m?

Homework Equations

F=ma
a=v^2/r in uniform circular motion

The Attempt at a Solution

Seems simple enough. To find the acceleration I simply squared the speed and divided by the radius. 2^2/2=2m/s^2.

This was graded as incorrect. What am I doing wrong? Am I confusing speed and velocity? Please help!

 

[Doc Al]

Looks fine to me. Was that the entire question?

 

[sleepingarmy]

Yup. I think the professor may have made a mistake. I'll take it to him. Thanks!