The document describes an experiment to investigate the relationship between current and the number of pins attracted to a soft iron rod inside a solenoid. The manipulated variable is current, the responding variable is the number of pins attracted, and the number of turns in the solenoid is kept constant. The procedure involves setting up the apparatus and recording the number of pins attracted at different current values ranging from 0.2A to 1.0A. The data is then tabulated and graphed with current on the x-axis and number of pins on the y-axis to analyze the relationship.

1. Strength of magnetic field / number of pin attracted and magnitude of current
Inference The strength of magnetic field depends on current.
Hypothesis The higher the current, the greater the number of pin attracted to the soft iron
rod.
Aim To investigate the relationship between the number of pin attracted to the soft
iron rod and magnitude of current.
Variables Manipulated variable: Current, I
Responding variable : Number of pin attracted, N
Constant variable : number of turn of the solenoid
List of
apparatus
and materials
Rheostat, ammeter, switch, dry cells, connecting wires, crocodile clips, soft
iron rod, solenoid, pins, petri dish and retort stand.
Arrangement
of the
apparatus
Procedure 1. The apparatus is set up as shown in the diagram.
2. The switch is closed and the rheostat is adjusted until the current I flows
in the circuit 0.2 A.
3. The petri dish is filled with pin and raised to the lower end of solenoid.
4. The number of pin attracted by the solenoid, N is recorded.
5. The experiment is repeated with current, I = 0.4 A, 0.6 A, 0.8 A and 1.0
A.
6. All the data are recorded and tabulated.
7. A graph of N against I is plotted.
Way to
tabulate the
data
I(A) N
0.2
0.4
0.6
0.8
1.0
Way to
analyse the
data
I/A
N