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GCSE physics

Can someone give me the answer for this question The picture shows an electric cooker hob. The simplified circuit diagram shows how the four heating elements connect to the mains electricity supply. The heating elements are all equal. When all four heating elements are switched on at full power the hob draws a current of 26 A from the 230 V mains electricity supply.Calculate the resistance of one heating element when the hob is switched on at full power. Give your answer to 2 significant figures.

Reply 1

Fifi06

Could someone please help me with this question it’s worth three marks

The picture shows an electric cooker hob. The simplified circuit diagram shows how the four heating elements connect to the mains electricity supply. The heating elements are identical.

When all four heating elements are switched on at full power the hob draws a current of 26 A from the 230 V mains electricity supply.

Calculate the resistance of one heating element when the hob is switched on at full power. Give your answer to 2 significant figures.

Reply 2

qeachy

are the heating elements in series? if so, the current running through each element is the same (26A) and the voltage is equally shared between elements (230/4= 57.5V). Put those values into the equation V=I^2R and do a bit of rearranging and you should get the resistance of one element.

Reply 3

qeachy

Original post by qeachy

if the elements are not in series or rather they are all parallel to each other (now that i think of it, that's probably the case) then you must divide the current by 4 (26/4) to get the current running through one element, and you use the value of 230 for the potential difference. this is because in a parallel circuit, the sum of the current running through each path is equal to the total current, but the voltage is the same across each component. you'll need to use your diagram to work this out. but you will eventually use the equation V=I^2R