Two loudspeakers are located 2.59 m apart on an outdoor stage. a listener is 21.6 m from one and 22.7 m from the other. during the sound check, a signal generator drives the two speakers in phase with the same amplitude and frequency. the transmitted frequency is swept through the audible range (20 hz to 20 khz). (a) what is the lowest frequency fmin, one that gives minimum signal (destructive interference) at the listener's location

Frequency

Explanation:

Given data:

The distance between the speakers, d = 2.59 m

The distance between the listeners, ΔL = 22.7 - 21.6 = 1.1 m

Now, For a destructive interference, we know that

where, λ = wavelength

thus,

frequency

where,

v = speed of sound = 343 m/s

for n = 1

we get

frequency

or

Frequency

a.metals can become magnetic if they have many spinning electrons that create magnetic fields.d.only some metals are attracted by magnets; these metals are called ferromagnetic.

d.wrapping an insulated wire around a metal with ferromagnetic properties and applying an electric current.

when two balls of the different masses are dropped from equal height, they reach the ground at the same time .this is because they experience the same acceleration.

the acceleration is independent of mass.

thus when they are dropped they will always maintain the same velocity and travel the same distance (neglect air resistance of course) at the same time.