Page 60 - Physics_Form_2
P. 60
Physics for Secondary Schools
using circuit symbols and label switch, voltmeter, rheostat,
all components. connecting wires
(b) Calculate the effective resistance Procedure
of the entire circuit.
(c) Use the readings to calculate the 1. Connect an electric circuit as shown
internal resistance r of the cell. in Figure 2.25.
FOR ONLINE READING ONLY
Resistance
Voltmeter
On
Ammeter R
Off
Figure 2.25
2. With the switch open, measure and
Figure 2.24
record the potential difference across
Potential difference across a conductor, the bulb and the current through the
current and resistance circuit by using the voltmeter and
Performing Activity 2.4 can determine ammeter, respectively.
the relationship between p.d across a 3. Close the switch and adjust the
conductor, the current flowing through rheostat until the voltmeter reads
the conductor, and the conductor’s 0.2 V.
resistance and performing activity 2.5 one 4. Measure and record the current
can determine the unknown resistance in through the bulb. Observe the
circuit by ohms law. brightness of the bulb.
5. Continue increasing the p.d at
Activity 2.4 intervals of 0.2 V up to 1.2 V by
adjusting the rheostat. Read the
Aim: To determine the
relationship between corresponding current value in each
potential difference, case.
current and resistance 6. Using a spreadsheet or otherwise,
Materials: a d.c. power supply or 1.5 record the results as shown in Table
V cell, ammeter, bulb, 2.1.
54
Student’s Book Form One
Physics Form 2 Final.indd 54 25/10/2025 10:26
