MHT CET202523 Apr 2025Morning ShiftPhysicsWaves and SoundActual
Two identical straight wires are stretched so as to produce 6 beats per second when vibrating simultaneously with tensions ' T ₁ ' and ' T ₂ ' respectively. On changing the tension slightly in one of them, the beat frequency remains unchanged. This will happen when (Given T ₁> T ₂ )
Options
- AT ₁ is increased or T ₂ is decreased
- BT ₁ is increased by 144
- CT ₂ is decreased by 144
- DT ₁ is decreased or T ₂ is increased
Correct answer
D. T ₁ is decreased or T ₂ is increased
Step-by-step solution
Problem Analysis: Given two identical wires with initial tensions T₁ > T₂ , the frequencies satisfy f₁ = C T₁ and f₂ = C T₂ , where C is a constant. The 6 Hz beat frequency implies f₁ - f₂ = 6 . Altering tension slightly while maintaining the beat frequency at 6 Hz implies a crossover in frequencies. If T₁ is changed, the frequency must decrease such that f₁' = f₂ - 6 , requiring T₁ to be decreased. If T₂ is changed, the frequency must increase such that f₂' = f₁ + 6 , requiring T₂ to be increased. The only consist