Question

A body of mass $\sqrt{3}$ kg is suspended by a string to rigid support. The body is pulled horizontally by a force F until the string makes an angle of ${30}^{\circ }$ with the vertical. The value of F and tension in the string are

• A. 9.8 N, 9.8 N
• B. 9.8 N, 19.6 N
• C. 19.6 N, 19.6 N
• D. 19.6 N, 9.8 N

Answer 1

The correct option is A 9.8 N, 9.8 N

$T\cos {30}^{\circ }=mg$
$T\times \frac{\sqrt{3}}{2}=\sqrt{3}\times 19.8$
$T=2\times 9.8$
$T=19.6N$
$T\sin {30}^{\circ }=F$
$F=19.6\times \frac{1}{2}$
$F=9.8N$