Problems 2: UNIZOR.COM - Physics4Teens - Electromagnetism - Magnetism and Electric Current
Channel: Zor Shekhtman on UNIZOR Education
Date: 2020-06-05

UNIZOR.COM - Physics through a Looking Glass of Mathematician

Notes to a video lecture on http://www.unizor.com

Parallel Currents - Problems 2

Problem 2A
Two ideally long and thin straight wires are parallel to each other and positioned at distance d from each other.
One wire carries an electric current of amperage I1.
Another wire carries an electric current of amperage I2 in the opposite direction.
Determine the magnitude of the repelling force between these two wires per unit of length of each.

Problem 2B
Two identical sufficiently long and thin straight wires of mass m per unit of length are horizontally hanging on threads of the same length L parallel to each other at the same height. The initial distance between them is d and they can swing on their corresponding threads parallel to themselves.
Initially there is no current in these wires and the threads holding these wires are in vertical position.
When we run electric current I through the first wire and the same in amperage electric current I through the second one in the opposite direction, the wires swing away from each other on their threads.
At equilibrium both threads made an angle φ with a vertical.
Determine the amperage I.