PHYSICS
JAMB 2000 - Question 18
Physics 2000 JAMB Past Questions - Question 18: A sonometer wire is vibrating at frequency fo. If the tension in the wire is doubled while the length and the mass per unit length are kept constant, the new frequency of vibration is
A:
B:
C:
D:
Correct Answer
D
Explanation
For a vibrating sonometer wire, the frequency
F = l/2l √(T/m)
and if the length, l and mass per unit length, m, are constant, then Fo ∝ √T => FoK√T or Fo/√T = K
=> F1o/√F1 = F2o/√F2
∴ F1o/√T1 = F2o/√T2
thus F2 =F3x√(2T1__√T1
==Fox√2 x √T1√T1
∴F2 = Fo x √2 = Fox√2

