Astring of mass m and length l is under tension t. the speed of a wave in the string is v. what will be the speed of a wave in the string if the mass of the string is increased to 2m, with no change in length?

Explanation:

The speed of a wave in a string is given by:

where

T is the tension in the string

m is the mass of the string

L is the length

In this problem, the mass of the string is increased to 2m: m' = 2 m, while the length is not changed, L'=L. If the tension in the string is not changed, then the new speed of the wave in the string will be:

so, the speed of the wave decreases by a factor

if the person is shown to have +90n, then ans is -10n.

if the person is shown to have -90n, then ans is +10n.