Current, potential difference and resistanceAQA A-Level Physics: Mind map

Exam questions on Current, potential difference and resistance

1. A mobile phone is charged for 40 minutes with a constant current of 1.5 A. The pd across the phone's battery is 3.7 V while it charges.
   State what is meant by a pd of 3.7 V across the battery, and calculate the energy transferred to the battery while 3.6 × 10³ C of charge flows through it.2 marks
2. A student connects a resistor to a power supply. When the pd across the resistor is 6.0 V, the current through it is 24 mA. The resistor is an ohmic conductor and its temperature stays constant.
   The pd of 6.0 V is applied for 5.0 minutes. Calculate the charge that passes through the resistor and the energy transferred to the resistor in this time.2 marks
3. A car starter motor is supplied by a 12 V battery. During one start the motor draws a constant current of 150 A for 3.0 s. The battery can supply a total charge of 1.6 × 10⁵ C before it is flat.
   Calculate the charge that flows through the starter motor during one start, the energy transferred to the motor, and the resistance of the motor circuit.3 marks