- #1
beckett
- 11
- 0
Hi folks,
Please, please help me, i know the answer to my question must have an easy answer but i can't figure it out.
Consider a simple circuit with a piece of copper wire, a switch and a battery. I know that when i close the switch the PD drives the electrons around the wire at a rate which is dependant on the total resistance of the wire. Heat will be produced as the electrons accelerate for short periods of time, collide with the copper atoms, then re-accelerate etc etc.
Now this makes me think that if the resistance of the wire was greater then there would be more collisions and hence more heat produced but when i do the calculations eg P=VI i can deduce that the opposite is true i.e. more heat is produced if i lower the resistance because the current will increase and thus the power will increase. This also makes sense to me as i can imagine as the electrons speed up they will collide with atoms at greater force and hence 'produce' more heat. The thing is i know that the latter is correct by experiment but can someone explain to me in easy terms what is happening and where i am going wrong in my thoughts?
Thanks in advance
Please, please help me, i know the answer to my question must have an easy answer but i can't figure it out.
Consider a simple circuit with a piece of copper wire, a switch and a battery. I know that when i close the switch the PD drives the electrons around the wire at a rate which is dependant on the total resistance of the wire. Heat will be produced as the electrons accelerate for short periods of time, collide with the copper atoms, then re-accelerate etc etc.
Now this makes me think that if the resistance of the wire was greater then there would be more collisions and hence more heat produced but when i do the calculations eg P=VI i can deduce that the opposite is true i.e. more heat is produced if i lower the resistance because the current will increase and thus the power will increase. This also makes sense to me as i can imagine as the electrons speed up they will collide with atoms at greater force and hence 'produce' more heat. The thing is i know that the latter is correct by experiment but can someone explain to me in easy terms what is happening and where i am going wrong in my thoughts?
Thanks in advance