Question

A bead released from one end of a frictionless rigid wire frame fixed in a vertical plane, slides periodically on the frame.Size of the bead is negligible as compared to the radius of curvature of the turns, which is negligible as compared to the length of straight portions of the frame. If linear dimensions of the frame are made four times, by what factor will frequency of periodic motion of the bead change?

• A. $4$
• B. $2$
• C. $1/4$
• D. $1/2$

Answer 1

The correct option is C $1/4$

Given,

Linear dimension $x$ is made four times

In periodic motion displacement is directly proportional to time

If linear dimension will change by 4 times than time will also change by 4 times

Now time period is inversely proportional to frequency therefore, if time will change by 4 time than frequency will change by (1/4) times.

Correct option is C.