If the current in a wire is directed upward, what is the direction of the magnetic field produced by the current?
A. counterclockwise
B. clockwise
C. in the same direction as the current
D. in the opposite direction to the current
D?
no d.
clockwise or counterclockwise depends if one is looking at the top or bottom. And, "current". normally in physics, we consider the direction of current as the direction of a positive charge carrier, knowing that in metals current is electrons, going in the opposite direction of the mythical + charges.
If you use the positive current convention, then the right hand rule (thumb in direction of current), fingers then curl in the direction of magnetic field lines.
Wow...my brain is fried and it took me a couple minutes to gather all the info into my brain of what you wrote hahaha
what does the deflection of the needle indicate when the switch is turned on?
Clockwise
Yes, the correct answer is D. The magnetic field produced by a current-carrying wire is always in the opposite direction to the current.
To understand why, you can use the right-hand rule.
Imagine holding the wire in your right hand, with your thumb pointing in the direction of the current. Your fingers will naturally curl around the wire in the direction of the magnetic field lines. In this case, since the current is directed upward, your fingers would point in the opposite direction, which is counterclockwise if you imagine looking down on the wire from above.
Therefore, the correct answer is D.