Question

To determine the resistance of a galvanometer by half deflection method readings

Answer 1

Resistance can be determined by the following procedure using Galvanometer:

1. You need to make connection according to the picture attached.
2. All the wires should be tightly connected to the boxes.
3. From the resistor box  take out the high resistance  (i.e 2500 ohms) and Key 1 should be inserted only.
4. Value of R should be adjusted so that maximum  deflection should be attained.
5. Let ∅ be deflection. Note ∅(theta).
6. Without changing the resistance,you need to insert the key and adjust the shunt resistance (S) such that the deflection becomes half the value obtained in step 5 . i.e(∅/2).
7. Note shunt resistance(S) value.
8. Repeat the step from 4 to 7 with different resistance and adjusting shunt resistance accordingly.