The ends of a string weighing w/metre are attached to two points at the same horizontal level. If the central dip is very small, the horizontal tension of the string throughout is
A
$$\frac{{{\text{w}}l}}{{4{\text{d}}}}$$
B
$$\frac{{{\text{w}}{l^2}}}{{4{\text{d}}}}$$
C
$$\frac{{{\text{w}}{l^2}}}{{8{\text{d}}}}$$
D
$$\frac{{{\text{w}}{l^2}}}{{16{\text{d}}}}$$
Correct Answer: $$\frac{{{\text{w}}{l^2}}}{{8{\text{d}}}}$$
