Current and potential differenceIB MYP Physics: Mind map

Exam questions on Current and potential difference

1. A camping torch has a small lamp that is powered by a 6.0 V battery. A family on a night walk in the Hajar Mountains switches the torch on and leaves it running for a short time.
   Calculate the energy transferred to the lamp when 60 C of charge passes through it from the 6.0 V battery.2 marks
2. A student builds a simple circuit from a cell, a switch and a lamp, joined together with copper wires. She wants to find out how charge moves in the wires and to measure the current through the lamp and the potential difference across it.
   State the direction of conventional current in the circuit and explain why this is opposite to the direction in which the electrons move.2 marks
3. A student investigates how the current through a small filament lamp depends on the potential difference across it. She connects the lamp to a variable power supply, with an ammeter and a voltmeter, and measures the current for four different values of potential difference.
   State a testable hypothesis for this investigation, give a scientific reason for it, and identify the dependent variable.3 marks