MHT CET Medical202624 April 2026Morning ShiftPhysicsWaves and SoundActual
Two identical straight wires are stretched so as to produce 8 beats per second when vibrating simultaneously with tensions T₁ and T₂ respectively. On changing the tensions, the beat frequency remains unchanged. This will happen when (T₁>T₂)
Options
- Aboth T₁ and T₂ is decreased by value 256 N
- Bboth T₁ and T₂ is increased by value 256 N
- CT₁ is decreased or T₂ is increased
- DT₁ is increased or T₂ is decreased
Correct answer
C. T₁ is decreased or T₂ is increased
Step-by-step solution
The frequency of a stretched wire is given by f = 1 2L T . Since T₁ > T₂ , the initial frequencies satisfy f₁ > f₂ . The initial beat frequency is f₁ - f₂ = 8 . For the beat frequency to remain unchanged after changing the tensions, the new frequencies must satisfy |f₁' - f₂'| = 8 . If T₁ is changed while T₂ is kept constant, we need |f₁' - f₂| = 8 . Since f₁ - f₂ = 8 , the only other possibility is f₂ - f₁' = 8 f₁' = f₂ - 8 = f₁ - 16 . This requires f₁ to decrease, meaning T₁ must be decreased. If T₂ is changed wh