Calculate Coulombs Law: Charge, Current, and Power in Electrical Circuits

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A charge of 4000μC is equivalent to 0.004 coulombs, calculated by converting microcoulombs to coulombs. The current in the wire is determined using the formula current = charge/time, resulting in 0.08 A. To find the number of electrons passing each point in the wire, the charge is divided by the electron charge (1.6 x 10^-19 C), yielding approximately 2.5 x 10^16 electrons per second. For the kettle, the current is calculated from the energy transferred (6.9 x 10^5 joules) over 5 minutes, resulting in a current of 23 A. The power of the electric bar fire, with a resistance of 50 ohms and connected to a 240V supply, can be calculated using the formula power = voltage^2/resistance, resulting in 1152 watts.
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Q1. A charge of 4000μC passes each point in a wire in 50s
Calculate: a) the charge in coulombs
b) The current in the wire
c) The number of electrons per second passing each point in the wire (Electron charge = 1.6 * 10^-19 C)
Q.2 A 240V kettle transfers 6.9*10^5 joules of energy in 5 minutes. What is the current in the kettle?
Q.3 When hot an electric bar fire has resistance of 50ohms. When connected to the mains supply (240V) what is its power?

Really struggling with this..
 
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I'm sure you can find these in your book:
current=charge/time
charge=(#electrons)(electron charge)
power=(current)(voltage)
power=work/time
 
bobaustin said:
I'm sure you can find these in your book:
current=charge/time
charge=(#electrons)(electron charge)
power=(current)(voltage)
power=work/time

I have been away a lot lately and have fallen behind a bit..
so a) = 4000/50=80 coulombs?
b) (#electorons=?)(4000)=??
c)
 
a) doesn't make sense. Charge where? Is this part of a bigger question?
 
It looks like (a) is trivial: 1 uC is 10^-6C
 

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