Question

A bead of mass 15g is sliding on a wire. It has a speed of 2.0m/s at A, and it stops as it reaches the point C. The length of the wire from A to C is 250cm. How large an average friction force opposed the motion of the bead?

Answer 1

Answer:

.12 N

Explanation:

Velocity goes from 2 m/s    to   0  m/s   so average velocity = 1 m/s

.250 m / 1 m/s  =  .25 second to stop

change in velocity / change in time = accel

  2 m/s / .25 sec =  8 m/s^2

F = ma

  = .015 kg *  8 m/s^2  = .12 N