Two wires are made of the same material and
have the same length but different radii. They
are joined end-to-end and a potential
difference is maintained across the
combination, which of the following quantity
that is the same for both wires is
A
potential difference
B
electric current
С
current density
electric field
D
Answers
Answer:
A is the answer of that question
The potential difference (p.d or V) is the same for both wires.
P.d is the amount of work done to bring about 1 coulomb charge from one point to another point of the electric field. Its SI unit is volt (v) and calculated as,
where is work done and is the electric charge
Also, the potential difference (V) can be defined in terms of resistance as the potential difference across a conductor when 1 ampere current produces 1 ohm resistance in a conductor.
Mathematically,
From the above, it can be concluded as the potential difference is directly proportional to the resistance if the electric current is constant (V∝R).
Furthermore, the resistance produced in a conducting wire is directly proportional to its length for constant temperature (R∝l).
Therefore, if two wires are made of the same material and have the same length but different radii, the potential difference will be the same for both wires.