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# Resistivity and resistance in parallel circuit question watch

1. Could anyone pls explain how to answer this question? I know how to answer it on the basis of current being split in each circuit but not with resistivity though.

Use the concept of resistivity to explain why two resistors in parallel have a lower resistance than either on their own.
2. Because the current is split between them, they each experience less current than they would have on their own. this means there are fewer electrons passing through them per second. Fewer collisions within the atoms of the wire and the electrons. Therefore less resisting power to the motion of these electrons through the material.

Its the same as you usually would explain it with the current being split. But i think they want you to go in detail about the collisions being made in the resistor
3. (Original post by BlobBlob69)
Because the current is split between them, they each experience less current than they would have on their own. this means there are fewer electrons passing through them per second. Fewer collisions within the atoms of the wire and the electrons. Therefore less resisting power to the motion of these electrons through the material.

Its the same as you usually would explain it with the current being split. But i think they want you to go in detail about the collisions being made in the resistor
Thanks a lot BlobBlob69! But how do I link it to the concept of resistivity?
I tried using the formula for resistivity (R x A)/ L but it does not have any much relation to current decreasing...
Could it it be that length is increasing since there are two circuits in parallel rather than one in series?
4. When you put two resistors in parrallel of say cross sectional area A, you are effectively doubling that cross sectional area to get 2A. Then using the resitivity equation you can see resistance decreases. Lower overall resistance results in higher current.
When you put two resistors in parrallel of say cross sectional area A, you are effectively doubling that cross sectional area to get 2A. Then using the resitivity equation you can see resistance decreases. Lower overall resistance results in higher current.
Thanks a lot Ladkus! Now my doubts are cleared!

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