Predict the direction of a force on a current carrying wire (1 Viewer)

Jouma47

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Hi

How would you answer this qeustion

describe how you would predict the direction of a force on a current-carrying wire that is at right angles to magnetic field

thanks
 

Riviet

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This is more like outlining but use the right hand palm rule or FBI rule to predict which direction the force will be. Since the force is at right angles to the magnetic field, the force is a maximum as long as there are not other forces acting upon it.
 

Jaymee

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use the right-hand rule:
point ur thumb in the direction of the current,
ur index finger in the direction of the magnetic field
and then ur mmiddle finger should automatically point in the direction of the force.

hope that was the answer u were lookin for.
 

Riviet

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hydrobiont said:
What's the FBI rule?
The FBI rule is also known as Fleming's left finger rule, I'll try and explain how to use it:
1. Grip your left hand into a fist with your thumb sticking straight out.
2. Straighten the finger next to the thumb.
3. Now position your left hand so your finger points to the right and the thumb points forwards/up.
4. Finally, uncurl the next finger nearest to your thumb halfway so it points towards you.
I'll use a diagram to help explain the 4 steps:

| These two lines represent your thumb - F
|
----------> The arrow is your finger - B
O The O represents your middle finger pointing out of the screen or towards you - I
- these two dashes represent the other 2 curled up fingers
-

So F is the direction of the force, B is the direction of the magnetic field, I is the direction of the current.
 

hydrobiont

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I thought it's called the FBI rule because it uses a weird hand gesture, even now I still think it is....hehe

But isn't it works the same as the right hand palm rule?
So which rule came out first? The right hand palm rule or the FBI rule?
 

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Jouma47 said:
Hi

How would you answer this qeustion

describe how you would predict the direction of a force on a current-carrying wire that is at right angles to magnetic field

thanks
would the wire slow down unless a force is applied, or slow momentarily and then continue at a constant speed?
 

helper

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The Left Hand rule came out first for any vector cross multiplication, where order of multiplication is important.

The General Right hand rule was a modification of this. The Right Hand Rule used by most people today is a specific case and is not useful for general cross multiplication, where BxI is not equal to IxB
 

Riviet

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hydrobiont said:
I thought it's called the FBI rule because it uses a weird hand gesture, even now I still think it is....hehe
I call it the FBI rule as well, but if you quote it in an exam or assessment, you should use the correct name so you don't risk losing a mark for that. :p
 
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maybach

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you can just use the right hand palm rule(rhpr)
you can only use this with your right hand.
1) open up your hand.
2)point your thumb in the direction of the current.
3)point your fingers in the direction of the magnetic feild(north to south)(can be in or out of page left or right up or down)
4) your palm will then tell you the force pointing out of your palm.

then just use F=bil (sine theta) to figure out the force in N(newtons)


hope i helped a bit:)
 

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