Answer:
a. Wavelength = λ = 20 cm
b. Next distance of maximum intensity will be 40 cm
Explanation:
a. The distance between the two speakers is 20cm. SInce the intensity is maximum which refers that we have constructive interference and the phase difference must be an even multiple of π and equivalent path difference is nλ.
Now when distance increases upto 30 cm between the speakers, the sound intensity becomes zero which means that there is destructive interference and equivalent path is now increased from nλ to nλ + λ/2.
This we get the equation:
(nλ + λ/2) - nλ = 30-20
λ/2 = 10
λ = 20 cm
b. at what distance, sound intensity will be maximum again.
For next point calculation for maximum sound intensity, the path difference must be increased (n+1) λ. The distance must increase by λ/2 from the point of zero intensity.
= 30 + λ/2
= 30 + 20/2
=30+10
=40 cm
Easy !
Take any musical instrument with strings ... a violin, a guitar, etc.
The length of the vibrating part of the strings doesn't change ...
it's the distance from the 'bridge' to the 'nut'.
Pluck any string. Then, slightly twist the tuning peg for that string,
and pluck the string again.
Twisting the peg only changed the string's tension; the length
couldn't change.
-- If you twisted the peg in the direction that made the string slightly
tighter, then your second pluck had a higher pitch than your first one.
-- If you twisted the peg in the direction that made the string slightly
looser, then your second pluck had a lower pitch than the first one.
Answer:
T = 693.147 minutes
Explanation:
The tank is being continuously stirred. So let the salt concentration of the tank at some time t be x in units of kg/L.
Therefore, the total salt in the tank at time t = 1000x kg
Brine water flows into the tank at a rate of 6 L/min which has a concentration of 0.1 kg/L
Hence, the amount of salt that is added to the tank per minute = 
Also, there is a continuous outflow from the tank at a rate of 6 L/min.
Hence, amount of salt subtracted from the tank per minute = 6x kg/min
Now, the rate of change of salt concentration in the tank = 
So, the rate of change of salt in the tank can be given by the following equation,
or, 
or, T = 693.147 min (time taken for the tank to reach a salt concentration
of 0.05 kg/L)
