Apipe 0.570 m long and closed at one end is filled with an unknown gas. the third lowest harmonic frequency for the pipe is 780 hz.
(a) what is the speed of sound in the unknown gas?
(b) what is the fundamental frequency for this pipe when it is filled with the unknown gas?

a. v = 355.68 m / s

b. fₙ = 156 Hz

Explanation:

Given

L = 0.570 m , f = 780 Hz

f = n * v / 4 * L

Solve to u' to find the speed of sound in the unknown gas

v = f * 4 * L / n

v = 780 Hz * 4 * 0.570 m / 5

v = 355.68 m / s

The fundamental frequency for this pipe when it is filled with the unknown gas

fₙ = f /n

fₙ = 780 Hz / 5

fₙ = 156 Hz

a solenoid is created by wrapping a l = 90 m long wire around a hollow tube of diameter d = 4.5 cm.   the wire diameter is d = 0.9 mm.   the solenoid wire is then connected to a power supply so that a current of i = 9 a flows through the wire.

randomized variablesl = 90 m

d = 4.5 cm

d = 0.9 mm

i = 9 a                                          

write an expression for the number of turns, n, in the solenoid. you do not need to take into account the diameter of the wire in this calculation.

calculate the number of turns, n, in the solenoid.

write an expression for the length of the solenoid (l2) in terms of the diameter of the hollow tube d.

calculate the length of the solenoid (l2)   in meters.

calculate the magnitude of the magnetic field at the center of the solenoid in teslas.

explanation: