Answer:
Charge on each metal sphere will be 
Explanation:
We have given number of electron added to metal sphere A 
As both the spheres are connected by rod so half -half electron will be distributed on both the spheres.
So electron on both the spheres 
We know that charge on each electron 
So charge on both the spheres will be equal to 
So charge on each metal sphere will be equal to 
Answer:The choke coil works because it can act as an inductor. When the current pass through will change as AC currents creates a magnetic field in the coil that works against that current. This is known as inductance and blocks most of the AC current from passing through.
Explanation:
Scientists could investigate this idea by making cathode ray tubes out of different materials to see if the ray was the same.
Answer:
"It will be more than the speed of sound waves in air at 20*C and water at 20*C."
Explanation:
Speed of sound in a medium depends upon the density and elasticity of the medium.
If the elasticity of a medium is greater and the density of that medium is lower, sound will travel faster. Although density is also a factor but the major factor is Elasticity.
Hence, sound travel faster in solids than in liquids and even slower in gases due to elasticity difference.

That is why the speed of sound in glass will be more than the speed of sound waves in air at 20*C and water at 20*C.