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Some hard questions here - that need a bit of detective work.  

Hints: -  remember that current is the same in all series parts of a circuit

          -  remember that the potential difference is the same across parallel parts

          -  remember that the potential difference across series parts will add up to the voltage of the supply 

For each of these circuits label the missing value of current, potential difference or resistance:

1.  Ammeter current = 0.3A, Cell voltage = 9V, Resistance of bulb = 


2.  Voltage of battery = 9V, Resistance of buzzer = 50 Ohms, Current = 0.05A 

Resistance of the motor =



3.  When switch is closed: p.d across bulb Y = 5V,  Resistance of bulb Y = 400 Ohms, Resistance of bulb X = 500 Ohms, 

P.d. across bulb X = 



4.  When switch is closed: Current flowing through circuit = 0.05A, Resistance of bulb X = 2 kilo Ohms, P.d. across bulb Y = 130V

Voltage of supply =



5.  Current flowing out of cell = 2.5A, Current flowing into top bulb is 0.5A, Resistance of top bulb = 10 Ohms

Resistance of lower bulb is

Press the button to check your answers:

Click to go to mains electricity