Why do transformers hum? Transformer noise is caused by a phenomenon which causes a piece of magnetic sheet steel to extend itself when magnetized. When the magnetization is taken away, it goes back to its original condition. This phenomenon is scientifically referred to as magnetostriction.
Answer:
Resistance in the flash tube, 
Explanation:
It is given that,
Speed of the bullet, v = 500 m/s
Distance between one RC constant, d = 1 mm = 0.001 m
Capacitance, 
The time constant of RC circuit is given by :

R is the resistance in the flash tube
..........(1)
Speed of the bullet is given by total distance divided by total time taken as :




Equation (1) becomes :


So, the resistance in the flash tube is
. Hence, this is the required solution.
Answer:
The wavelength in miles is <u>0.1165 miles</u>.
Explanation:
Given:
Wavelength of the radio wave is 187.37 m.
Now, the wavelength is given in meters.
We need to convert the wavelength from meters to miles.
In order to convert meters to miles, we have to use their conversion factor.
We know that,
1 meter = 
Therefore, the conversion factor is given as:

So, the wavelength in miles is given as:

Hence, the wavelength in miles is 0.1165 miles.