A galvanometer of resistance, g, is shunted by a resistance s ohm. To keep the main current in the circuit unchanged, the resistance to be put in series with the galvanometer is
Answers
s ohm is connected in parallel as shunt to the galvanometer. so, let R is the resistance introduced in series with galvanometer.
final resistance = intial resistance (g)
so,
R + gs/(g+s) = g
=> R = g { 1 - s/(g+s)}
= g { (g + s - s)/(g +s)}
= g^2 / (g+s)................... ans...
Answer: The value of the resistance which is parallel with the galvanometer is R=(G^2)÷(G+S)
Explanation:
The resistance of the galvanometer is G
The galvanometer is shunted by a resistance which is parallely connected to the galvanometer. The resistance of the shunt is S.
To put the main current unchanged a resistance is need to be connected to the galvanometer is series. Let assume the resistance of this resistor is R.
So,
=>{GS÷(S+G)}+R=G
=>R=G-{GS÷(S+G)
=>R=(G^2+GS-GS)÷(G+S)
=>R=(G^2)÷(G+S)