PHYS 1510 Lecture Notes - Lecture 7: Charge Carrier, American Association Of Variable Star Observers, Butea Monosperma

consider the 2 very long parallel wires shown below.

the wires carry equal currents in opposite directions and thecurrent in wire 1 is directed to the right. the wires are seperatedby distance D. 3 points are shown on the diagram
A) inside wire 1 B) located directlybewteen the 2 wires C) islocated D/2 from wire 2.

1. what is the total magnetic field at location B?

2. What is the total magnetic field at location C?

3. what is the magnetic field caused by wire 2 at A?

4. what force does wire 1 experience due to the presence of wire2? what is the mechaniam of this force?

5. what force does wire 2 experience?

6. if the current were 2 amps and the distance is 1.5 cm, whatis the force on wires 1 and 2? what is the magnetic field at C?

1 - A compass in a magnetic field will line up __________.

(A) - with the north pole pointing perpendicular to the magnetic field

(B) - with the north pole pointing opposite the direction of the magnetic field

(C) - with the north pole pointing in the direction of the magnetic field

2 - The magnetic field lines due to a straight, current-carrying wire are __________.

(A) - straight lines parallel to the wire

(B) - circles around the wire

(C) - straight lines perpendicular to the wire

3 - Two parallel wires carry a current in the same direction. There is ___________ between the wires.

(A) - a repulsive force

(B) - no force

(C) - an attractive force

4 - The direction of the magnetic force on a moving charged particle in a magnetic field is __________.

(A) - both perpendicular to the velocity and perpendicular to the magnetic field

(B) - perpendicular to the magnetic field

(C) - perpendicular to the velocity

In Procedure 1: a wire of length L = 3.91 cm sits on an electronicscale. There is also a uniform mangetic field perpendicular to thewire, and along its entire length. When there is no current in thewire, the scale reads 573 g. When a current I = 48.2 mA goesthrough the wire, and the scale reads 544 g.
NOTE: Beware of units!

a) Find F, the magnitude of the force on the wire created by theinteraction of the current and the magnetic field.
____ N

b) Find B, the magnitude of the magnetic field around thewire.
_________T

c) Suppose the direction of the magnetic field is reversed. Whatwould the scale read now?
___________ g

d) Suppose the system could take large currents. To what would youhave to raise the current (before you reversed the direction of B)so the force on the wire entirely supported the weight of the wire(and the scale reads zero)?
_________A