Magnet - right hand rule - direction of compass North

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SUMMARY

The discussion centers on determining the direction of the compass needle's North pole when placed beneath a current-carrying loop of wire. The loop, viewed from above, runs from left to right with a clockwise current. Applying the right-hand rule, the thumb points to the right, indicating that the magnetic field direction is out of the screen, causing the compass's North pole to point toward the top of the monitor. The conclusion is that the correct answer is option d) "toward the top of the monitor."

PREREQUISITES
  • Understanding of the right-hand rule in electromagnetism
  • Familiarity with magnetic fields generated by current-carrying conductors
  • Knowledge of conventional current flow versus electron flow
  • Basic concepts of magnetic field direction relative to current direction
NEXT STEPS
  • Study the right-hand rule in detail for various current configurations
  • Explore the principles of magnetic fields around loops of wire
  • Learn about the effects of current direction on magnetic field orientation
  • Investigate applications of magnetic fields in practical scenarios, such as electric motors
USEFUL FOR

Students of physics, educators teaching electromagnetism, and anyone interested in understanding the behavior of magnetic fields around current-carrying conductors.

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Homework Statement


A length of wire extends upward through a piece of cardboard, bends around, forming a loop, and extends back down through the cardboard. All that is visible above the surface of the cardboard is this loop of wire. From your perspective, you are looking downward on the piece of cardboard so the loop runs from your left to your right. The loop of wire has a current running through it in a clockwise direction (from left to right above the cardboard). If a compass is placed on the cardboard beneath the loop, in which direction will the N pole of the compass point?

a) It will point toward the right of the monitor.
b) It will point toward the left of the monitor.
c) It will point toward the bottom of the monitor.
d) It will point toward the top of the monitor.


Homework Equations


Right hand rule.


The Attempt at a Solution


I did the right hand rule and pointed my thumb to the right. My fingers were then pointing "out" of the screen. So the answer is either "toward the top of the monitor" or "toward the bottom of the monitor". I think it's toward the bottom, but I'm not sure and can't risk getting this question wrong. Can anyone help me?
Thanks!
 
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I see others are avoiding this question and it is about to slip off the first page. No wonder; it is quite unclear! Do we have a loop of wire lying in the plane of the cardboard so the "monitor" looking down sees a circle of wire? Or is it a loop standing up perpendicular to the cardboard so the observer sees a line of wire going left to right; likely the loop is completed right to left underneath the cardboard in this scenario. In the first case, the magnetic field would be up toward the monitor or down away from it (depending on whether the current is conventional positive current or electron flow), so none of the choices are correct. Must be the second case! Picture your thumb (left or right hand depending on the type of current) going to the right, fingers wrapped around the wire. For positive current, the fingers go away from you (toward the top of the monitor) under the wire, and toward you above the wire. That should give you the answer, using your class convention for positive/negative current flow.
 

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