Ohm's law
Ohm’s law is a prominent concept in physics and electronics. It gives the relation between the current and the voltage. It is used to analyze and construct electrical circuits. Ohm's law states that the voltage across a conductor is directly proportional to the current flowing through it.
Path of Least Resistance
In a series of alternate pathways, the direction of least resistance is the actual or metaphorical route that offers the least resistance to forwarding motion by a given individual or body.
A copper wire 100m long with cross-sectional area of 2x10-4 cm2 is heated from room temperature of 250 C to 2000 C. Find
- The initial resistance of wire
- The increase in resistance from 25 to 200 C
Resistance of wire at room temperature is given as:
where is the resistivity, l is the length and A is the area of cross-section
The standard value of resistivity of copper is
Part 1.
given values are ,
So,
Step by step
Solved in 2 steps