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    1) A current of 5.5mA5.5mA is flowing through a resistance of 220kΩ Find the potential difference (in volts) across the resistance.

    5.5 mA =5,500,000 A , 220 kohms =220,000 ohms. P.D= IxV, = 5,500,000 X 220,000 = 1.21 X 10^12 Volts
    i got : 1.21x10^12. but it says sig figs are incorrect? WHERE have i gone wrong???


    2) The current flowing in a circuit is 10mA. Find the charge (in C) passing a point in the circuit in a time of 100μs i got 1000 which is incorrect?? 10,000,000 x (1x10^-4) = 1000? which is the amperes x seconds.
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    (Original post by poonshark)
    1) A current of 5.5mA is flowing through a resistance of 220kΩ Find the potential difference (in volts) across the resistance.

    5.5 mA =5,500,000 A , 220 kohms =220,000 ohms. P.D= IxV, = 5,500,000 X 220,000 = 1.21 X 10^12 Volts
    i got : 1.21x10^12. but it says sig figs are incorrect? WHERE have i gone wrong???


    2) The current flowing in a circuit is 10mA. Find the charge (in C) passing a point in the circuit in a time of 100μs i got 1000 which is incorrect?? 10,000,000 x (1x10^-4) = 1000? which is the amperes x seconds.

    Hi,

    I would suggest you learn the prefix correctly before attempting these questions.

    5.5 mA = 5.5*10^-3 A

    100 μs = 100*10^-6 s
 
 
 
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