How Does Current Direction Affect Magnetic Field Orientation?

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Suyash Singh

Homework Statement



current in wire is in east to west direction.direction of magneetic field below the line

Homework Equations


right hand thumb rule

The Attempt at a Solution


i used the right hand thumb rule to find the direction of magnetic field but the magnetic field comes out in in the upwards direction(out of plane) but the answer is in the south direction
my answer -upwards
real answer-south

Thankyou
 
Suyash Singh said:

Homework Statement



current in wire is in east to west direction.direction of magneetic field below the line

Homework Equations


right hand thumb rule

The Attempt at a Solution


i used the right hand thumb rule to find the direction of magnetic field but the magnetic field comes out in in the upwards direction(out of plane) but the answer is in the south direction
my answer -upwards
real answer-south

Thankyou
East to West defines a line, what plane do you speak about?
 
Suyash Singh said:
in in the upwards direction(out of plane)
Plane of the paper?
I think your answer is right.
 
cnh1995 said:
Plane of the paper?
I think your answer is right.
The paper can be horizontal, vertical, or can stand in any direction.

East, West, North, South are defined in a horizontal plane.
The magnetic field lines are circles around the wire, with the wire as axis. Take a pencil as wire and do the right thumb rule in reality. In what direction do your fingers point under the wire?
This is a very bad drawing, I was not able to make a better one. The wire and the cardinal directions are in the horizontal plane.
Diagram of a horizontal black line with arrowheads labelled W on the left and E on the right, with N above and S below, and pink hand-drawn scribbles and a curved arrow over the line.
 
ehild said:
East to West defines a line, what plane do you speak about?
the plane of paper since north south east west are in plane of paper.
 
Printed text reading: The current is flowing from East to West. The point is below the power line. Hence, according to Maxwell's right hand thumb rule, the direction of the magnetic field is towards the South.

this is the answer but my fingers are coming out of the plane of paper
like this
Right-hand grip rule diagram: a hand wraps around a red conductor carrying current from a battery, with the Direction of Current arrow pointing left and the Direction of Magnetic Field curled arrows shown around the wire.

and this the actual question
Printed problem text: A horizontal overhead power line carries a current of 90 A in east to west direction. What is the magnitude and direction of the magnetic field due to the current 1.5 m below the line?

I could get the numerical answer but not the the direction
 
Suyash Singh said:
View attachment 206877
this is the answer but my fingers are coming out of the plane of paper
like this
View attachment 206878
and this the actual question
View attachment 206879
I could get the numerical answer but not the the direction
Your fingers come out of the paper beside the wire or above it. Just under the wire the fingers stand in the North-West direction, and having short fingers, the tips would point to the South. The green vector represents the direction of the magnetic field under the wire.
Right-hand rule diagram: a hand grips a red-orange wire loop connected to a car battery, with arrows showing the current direction and the circular magnetic field direction, and a green arrow below the wire.


This is a side view:

Diagram of a wire seen end-on as a black circle with a dot, showing current out of the page, with green circular arrows around it labelled above the wire and under the wire, plus a line marked W and E.