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gcse aqa physics

can anyone please explain what happens to the p.d and current if resistance increases, i really don't get it and i keep seeing different answers. and is it different based on whether its an ohmic conductor?
Reply 1
In an ohmic conductor, the temp is constant so the p.d and current are directly proportional ( when one increases the other increases) so the resistance is constant ( because the electrons don’t have a change in kinetic energy for more/ less collisions with the ions in the wire), but in for example a bulb when the current increases the temp increases so the resistance increases because the electrons in the wire have more kinetic energy ( from temp) and collide more often with the ions in the wire.
Reply 2
so the pd and current decrease
Original post by nmaaa
In an ohmic conductor, the temp is constant so the p.d and current are directly proportional ( when one increases the other increases) so the resistance is constant ( because the electrons don’t have a change in kinetic energy for more/ less collisions with the ions in the wire), but in for example a bulb when the current increases the temp increases so the resistance increases because the electrons in the wire have more kinetic energy ( from temp) and collide more often with the ions in the wire.

okay thank you so so much! also, sorry to be annoying, but i just have another question. if you add a voltmeter to a series circuit does it become a parallel circuit and the whole circuit follows the rules for a parallel circuit? and in a parallel circuit, if components are connected in series in a branch does the p.d split?
thank you :smile:
Reply 4
Original post by jajahjhajhsja
okay thank you so so much! also, sorry to be annoying, but i just have another question. if you add a voltmeter to a series circuit does it become a parallel circuit and the whole circuit follows the rules for a parallel circuit? and in a parallel circuit, if components are connected in series in a branch does the p.d split?
thank you :smile:

the whole circuit does not become a parallel circuit as the voltmeter is only used to read the voltage of a component in a circuit, the circuit will still follow the rules of a series circuit.
Reply 5
Original post by jajahjhajhsja
okay thank you so so much! also, sorry to be annoying, but i just have another question. if you add a voltmeter to a series circuit does it become a parallel circuit and the whole circuit follows the rules for a parallel circuit? and in a parallel circuit, if components are connected in series in a branch does the p.d split?
thank you :smile:

in a parallel circuit the voltage (p.d) is the same everywhere it is only the current that splits equally at each branch
Original post by Tiya..x
the whole circuit does not become a parallel circuit as the voltmeter is only used to read the voltage of a component in a circuit, the circuit will still follow the rules of a series circuit.

honestly thank you soooo much !!! that's so helpful

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