Metre Bridge
Ex.No
Date
Aim:
To find resistance of a given wire using metre bridge and hence determine the specific resistance of its material.
Apparatus:
A meter bridge ,a Leclanche cell , a galvanometer ,a resistance box, a jockey, a resistance wire or resistance coil, a metre scale, a set square and connecting wires
Procedure:
1.Draw the circuit diagram as shown in figure and arrange the apparatus according to the arrangement diagram.
2. Connect the resistance wire or resistance coil whose resistance is to be determined in the right gap between C and D
3. Connect the resistance box in the left gap between A and D
4 Make all the connections as e shown in the circuit diagram.
5. Take out some resistance (say 2 ohm) from the resistance box, plug the key K.
6. Touch the jockey gently first at left and then at right end of the bridge wire.
7. Note the deflections in the galvanometer .if the galvanometer shows deflections in opposite directions, the connections are correct.
8. Move the jockey gently along the wire from left to right till galvanometer gives no deflection.The point where the jockey is touching the wire is null point B.
9.Choose an appropriate value of R from the resistance box such that there is no deflection ihe galvanometer when the jockey is nearly in the middle of the wire(between 40 cm and 60 cm)
10.Note position of point B (with the help of a set square)to know the length AB =L1
11. Take at least four sets of observations in the same way by changing the values of R.
12.Record your observations in the table given below
13.Measure the length of the wire L.
14.Measure the diameter of the wire D at least at four places ,in two mutual perpendicular directions at each place. 15 .Unknown resistance =R×l2l1, Where l2 =100 -l1 16.specific resistance of the material of the given wire= ρ=XD24L Percentage error=ρ-ρ0ρ0 ×100 Whereρ0 is standard value of the specific resistance of the material. Result : 1. The value of
Date
Aim:
To find resistance of a given wire using metre bridge and hence determine the specific resistance of its material.
Apparatus:
A meter bridge ,a Leclanche cell , a galvanometer ,a resistance box, a jockey, a resistance wire or resistance coil, a metre scale, a set square and connecting wires
Procedure:
1.Draw the circuit diagram as shown in figure and arrange the apparatus according to the arrangement diagram.
2. Connect the resistance wire or resistance coil whose resistance is to be determined in the right gap between C and D
3. Connect the resistance box in the left gap between A and D
4 Make all the connections as e shown in the circuit diagram.
5. Take out some resistance (say 2 ohm) from the resistance box, plug the key K.
6. Touch the jockey gently first at left and then at right end of the bridge wire.
7. Note the deflections in the galvanometer .if the galvanometer shows deflections in opposite directions, the connections are correct.
8. Move the jockey gently along the wire from left to right till galvanometer gives no deflection.The point where the jockey is touching the wire is null point B.
9.Choose an appropriate value of R from the resistance box such that there is no deflection ihe galvanometer when the jockey is nearly in the middle of the wire(between 40 cm and 60 cm)
10.Note position of point B (with the help of a set square)to know the length AB =L1
11. Take at least four sets of observations in the same way by changing the values of R.
12.Record your observations in the table given below
13.Measure the length of the wire L.
14.Measure the diameter of the wire D at least at four places ,in two mutual perpendicular directions at each place. 15 .Unknown resistance =R×l2l1, Where l2 =100 -l1 16.specific resistance of the material of the given wire= ρ=XD24L Percentage error=ρ-ρ0ρ0 ×100 Whereρ0 is standard value of the specific resistance of the material. Result : 1. The value of