Question

Two person are holding a rope of negligible weight tightly at its ends so that it is horizontal. A 15 kg weight is attached to the rope at the mid-point which now no longer remains horizontal. The minimum tension required to completely straighten the rope is:

• A. $sin=0$
• B. $\frac{15}{2}kg$
• C. $5kg$
• D. Infinitely large

Answer 1

The correct option is A $sin=0$

The tension required to bring the string into horizontal position can be found out using the following formula.

$2Tsinx=mg$

The following equation is true for body which attains equilibrium. Also, when the body will be in equilibrium the angle formed will be 0.

Therefore,

$T=\frac{mg}{2sinx},$ where $x=0$

$T=\frac{mg}{2sinx},$ where the value of $sin0=0$

Then,the amount of tension required is infinite.