Question

Two point size bodies of same mass are knotted to a horizontal string, one at the end, and the other at it's mid point. The string is rotated in a horizontal plane with the other end as centre. If $T$ is tension in the string between centre of circle and the first body then the tension in the string between the two bodies is:

• A. $\frac{T}{2}$
• B. $2T$
• C. $\frac{2T}{3}$
• D. $\frac{3T}{2}$

Answer 1

The correct option is C $\frac{2T}{3}$

$T-T_1=m{r}_1{\omega }^2=m\frac{L}{2}{\omega }^2$

$T_1=m{r}_2{\omega }^2=mL{\omega }^2$

$T=\frac{3mL}{2}{\omega }^2$

$mL{\omega }^2=\frac{2T}{3}=T_1$

$\therefore T_1=\frac{2T}{3}$