Q. One end of string of length l is connected to a particle of mass 'm' and the other end is connected to a small peg on a smooth horizontal table. If the particle moves in circle with speed 'v', the net force on the particle (directed towards center) will be (T represents the tension in the string)
A) T
B) T + $\frac{mv^2}{l}$
C) T - $\frac{mv^2}{l}$
D) Zero
Explanation
[Solution] On a smooth horizontal table the only horizontal force is the tension, which provides the centripetal force. Answer (1).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.