Choose the Most appropriate answer.
In a tube when a sound wave is created, compression and rarefaction pulses are produced. The rarefaction pulse has pressure.
Choose the Most appropriate answer.
In a tube when a sound wave is created, compression and rarefaction pulses are produced. The rarefaction pulse has pressure.
The correct option is D Minimum but greater than 0
When there is no wave in the tube we assume it only contains air molecules inside it, doesn't have a particle direction of motion. There is no pressure variation. The average pressure is P0 throughout.
When disturbance is created at one end it travels through the pipe in form of compression and rarefaction.
The pressure in the compressed region rises a certain value above the average pressure and in rarefaction it decreases by the exact same value below the average pressure.
This variation is sinusoidal.
P(x,t)=P0+ΔP0 sin ω (t−xv)
So in rarefaction sin ω (t−xv) will be negative
P(x,t)=P0−ΔP0 sin ω(t−xv)
The total pressure would have gone below the average pressure but still there will be some positive pressure as you know from fluids chapter that pressure exists due to the presence of particles. In a completely vacuum region pressure will be 0 but here in rarefaction region the density of air molecules has reduced but not become 0. So its d option, pressure is minimum but not 0
Minimum but greater than 0
When there is no wave in the tube we assume it only contains air molecules inside it, doesn't have a particle direction of motion. There is no pressure variation. The average pressure is P0 throughout.
When disturbance is created at one end it travels through the pipe in form of compression and rarefaction.
The pressure in the compressed region rises a certain value above the average pressure and in rarefaction it decreases by the exact same value below the average pressure.
This variation is sinusoidal.
P(x,t)=P0+ΔP0 sin ω (t−xv)
So in rarefaction sin ω (t−xv) will be negative
P(x,t)=P0−ΔP0 sin ω(t−xv)
The total pressure would have gone below the average pressure but still there will be some positive pressure as you know from fluids chapter that pressure exists due to the presence of particles. In a completely vacuum region pressure will be 0 but here in rarefaction region the density of air molecules has reduced but not become 0. So its d option, pressure is minimum but not 0
