Answer:
Telegraph distance will be 9.6 mile
Explanation:
We have given the voltage V = 9 volt
Contact resistance = 4 ohm
Relay resistance = 80 ohm
And wire has a resistance = 10 ohm/mile
We have given the current = 50 mA =0.05 A
According to ohm's law 
So the resistance of wire = 180-4-80=96 ohm
So the length of the telegraph distance will be 
Answer:
If you are standing next to loud music you will feel yourself vibrating because resonance happens. When an object vibrating at or near the resonant frequency of a second object then it causes the second object to vibrate. This phenomenon is called resonance.
Explanation:
Hope this helped! :))
Answer:
electric current is derived unit.
Explanation:
According to the definition of electric current, it appears to be a derived quantity. Charge on the other hand seems more fundamental than electric current.
