Kindly solve this question "

Dear student,

Wavelength of standing wave = λ, Frequency =f
Tension in string =T
Velocity of standing wave =√Tμ
v = λf
⇒λ∝√T
Thus on doubling T:λnew=√2λ

Spacing between 2 nodes = λ2
Thus new spacing = √2x

Hence,b option is correct.

Regards.