School
Class (No.)
( )
Name
Subject
AL Practical Physics
Date
Mark
C15 Investigation of magnetic fields by search coil
Procedure
A. Magnetic field around straight wire
4. Switch off the time base of the CRO. Record the length of the vertical trace shown on the CRO, which represents the induced peak-to-peak e.m.f. (V) in the search coil and also the magnetic field around the straight wire.
5. Repeat steps 2 to 4 with the other values of currents (I) from the signal generator in steps of 0.1 A. Tabulate the results.
Current (I) / A
0.5
0.6
0.7
0.8
0.9
.0
Induced e.m.f. (V) / mV
3.0
6.0
8.5
21.0
23.0
26.0
6. Plot a graph of the induced e.m.f. (V) against the current (I).
7. Repeat steps 2 to 4 with the other values of distances (r) of the search coil away from the straight wire. Tabulate the results.
Distance (r) / cm
2
3
4
5
6
/r / cm?1
.00
0.50
0.33
0.25
0.20
0.17
Induced e.m.f. (V) / mV
3.0
7.0
5.0
4.0
3.5
3.0
8. Plot a graph of the induced e.m.f. (V) against the reciprocal of distance ().
9. Vary the frequency of the signal generator. Describe how the sensitivity of the search coil changes.
Class (No.)
( )
Name
Subject
AL Practical Physics
Date
Mark
C15 Investigation of magnetic fields by search coil
Procedure
A. Magnetic field around straight wire
4. Switch off the time base of the CRO. Record the length of the vertical trace shown on the CRO, which represents the induced peak-to-peak e.m.f. (V) in the search coil and also the magnetic field around the straight wire.
5. Repeat steps 2 to 4 with the other values of currents (I) from the signal generator in steps of 0.1 A. Tabulate the results.
Current (I) / A
0.5
0.6
0.7
0.8
0.9
.0
Induced e.m.f. (V) / mV
3.0
6.0
8.5
21.0
23.0
26.0
6. Plot a graph of the induced e.m.f. (V) against the current (I).
7. Repeat steps 2 to 4 with the other values of distances (r) of the search coil away from the straight wire. Tabulate the results.
Distance (r) / cm
2
3
4
5
6
/r / cm?1
.00
0.50
0.33
0.25
0.20
0.17
Induced e.m.f. (V) / mV
3.0
7.0
5.0
4.0
3.5
3.0
8. Plot a graph of the induced e.m.f. (V) against the reciprocal of distance ().
9. Vary the frequency of the signal generator. Describe how the sensitivity of the search coil changes.