Consider two long parallel wires with the same length carrying currents of diffe
ID: 1383090 • Letter: C
Question
Consider two long parallel wires with the same length carrying currents of different magnitudes. The magnitude of the force that one wire exerts on the other is Fo.
1) If the current in both wires is halved, what happens to the magnitude of the magnetic force ( in terms of Fo) that each wire exerts on the other?
2) If the current in one wire is quadrupled and the current in the other wire is halved, what happens to the magnitude of the magnetic force ( in terms of Fo) that each wire exerts on the other?
Explanation / Answer
Let I1 and I2 are the currents in the wires.
Fo = mue*I1*I2*L/(2*pi*d)
1) when currents are halfed
F = mue*(I1/2)*(I2/2)*L/(2*pi*d)
= Fo/4 <<<<<<<----------Answer
2) When the current in one wire is quadrupled and the current in the other wire is halved
F = mue*(4*I1)*(I2/2)*L/(2*pi*d)
= 2*Fo <<<<<<<----------Answer