14. A spring has a force constant of 100N/m and an unstretched length of 0.07 m . One end is attached to a post that is free to rotate in the center of a smooth table, as shown in the top view above. The other end is attached to a 1 kg disc moving in uniform circular motion on the table, which stretches the spring by 0.03 m . Friction is negligible. What is the centripetal force on the disc?
(A) 0.3 N
(B) 3 N
(C) 10 N
(D) 300 N