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Electricity

I have this question that i dont understand:
A 36W lamp draws a constant current of 3.0A over a period of 600s from a battery. Calculate the number of electrons passing through the lamp.

I have already worked out: the p.d across the lamp= 12V
the energy transferred by the lamp= 21600J
the charge passing through the lamp= 1800C

thanks in advance
Reply 1
Avatar for alex193
alex193
17
1A = 1 coulomb per second, so for 3A in 600s how many coulombs?
Then 1 coulomb = how many electrons? (remember - 1 elementary charge = 1.602x10^-19 C)
Multiply these together and you're sorted.


I think :wink:
(edited 11 years ago)
Original post by alex193

***


I see this is your first post in the physics study help section.
Thanks for helping.

However...
Can I direct you to the guidance notes for posting here
http://www.thestudentroom.co.uk/wiki/Study_Help_Guidelines#answering_questions

in particular the request not to provide complete solutions to numerical problems. The aim is to help the poster help himself. As he had almost got to the solution, a small prod in the right direction was all that was needed.
Thanks for your cooperation.
Reply 3
Avatar for alex193
alex193
17
Oops, should probably have read that first :ashamed2:
Original post by alex193
Oops, should probably have read that first :ashamed2:


There may still be time to edit your post and simply delete the last line.

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