The speed 'v' of the waves in the string depends upon the tension, F, of the string and m, the mass per unit length of the string. It is given by:

Explanation

Option A) This is a standard formula. The speed v of the waves in the string depends upon the tension, F, of the string and m, the mass per unit length of the string. It is given by:v= √F/mtaking square on both sides of the equation:v²=F/mTherefore Option A is the correct option.Option B) v = F/m is incorrect because the equation for the speed of waves in a string includes a square root sign, which is missing in this option.Option C) v x m = F is incorrect because this equation is not dimensionally consistent. The left side has units of length times mass per unit time (velocity multiplied by mass per unit length), while the right side has units of force.Option D) v = F x m is also incorrect because this equation does not include the square root sign that is necessary to calculate the speed of waves in a string.