GCSE Physics - Charge, Current & Time #16

this video is going to be a really quick one to go over what charges and the equation that we use to find it if we go for the definition first charge is a measure of the total current that flowed within a certain period of time so if you're familiar with the water analogy where current is the rate at which water is flowing through the river then the charge would be the total amount of water that's flowed down the hill within a certain period of time like a minute or an hour we represent charge with the

letter q and is measured in coulombs which we show with a c the equation to remember is that charge equals current measured in amps multiplied by time measured in seconds so a question might look something like this a kettle draws a current of 12 amps and takes 50 seconds to boil how much charge passed through the wire well as we're already given the current in amps and the time in seconds all we do is plug the numbers into the equation so 12 times 50 which gives us 600 coulombs or for another question a phone charger

transfers a total charge of 43.2 kilo coulombs over a period of two hours what current flowed through the wire first we need to look at our equation and because we're trying to find current we're going to have to rearrange it into the right form by dividing both sides by time this gives us i equals q over t next we need to convert our units to get coulombs and seconds so we need to multiply 43.2 by 1000 to give us 43 to 200 coulombs and we need to multiply our two hours by 60 to get 120

minutes and then 60 again to get seconds which gives us 7 200 seconds and lastly all we have to do is plug the numbers in and do 43 200 divided by 7200 which gives us six amps and that's all for this video so if you enjoyed it then please do like and subscribe and we'll see you soon you