A physics class is investigating the combined resistance of two identical resistors arranged either in series or in parallel.
A student sets up the resistors in a parallel circuit (Circuit A) under a specific voltage. The voltage across the parallel combination is measured as Vp=3.0 VV_p = 3.0\text{ V}Vp=3.0 V and the total current from the source is Ip=0.60 AI_p = 0.60\text{ A}Ip=0.60 A.
Next, the student rearranges the same two resistors into a series circuit (Circuit B). The readings are recorded as:
State the standard SI symbols used for the units of voltage, current, and resistance.
Calculate the combined resistance of the resistors for both configurations:
Calculate the ratio yyy of the resistances using the equation:
y=RsRp y = \frac{R_s}{R_p} y=RpRsAn engineer sets up a test circuit containing two DC motors connected in parallel to a power source. An ammeter is connected to measure the total circuit current, and a variable resistor is placed in series with the power source.
State the primary purpose of the variable resistor in this control circuit.
Describe how a voltmeter should be connected to measure the potential difference across one of the motors.
52 exam-style questions on CIE IGCSE Physics 4.3.2a Series circuits. Each one has a worked solution and a mark scheme showing where the marks go.