Question

A particle of mass $m$ connceted with the help of string of length $l$ is released from rest, when string is horizontal. Tension in string when particle is at lowest point, is

• A. $2mg$
• B. $3mg$
• C. $mg$
• D. $\frac{4}{3}mg$

Answer 1

The correct option is B $3mg$

Applying conservation of mechanical energy
$\frac{1}{2}m{v}^2=mgl$


When the string is horizontal,
$T-mg=\frac{m{v}^2}{l}$

$T=3mg$