Author Topic: Physics help  (Read 3862 times)

Offline yinyang

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Re: Physics help
« Reply #15 on: May 06, 2009, 12:09:12 pm »

gamma rays- never deflect in either magnetic or electric fields.

flemings left hand rule-

hold your left hand such the your thumb first and middle finger are perpendicular to each other. the thumb represents the direction of deflection the first finger represents the direction of the magnetic field i.e. from N to S and the middle finger represents the direction of conventional current.note that a beta particle is an electron so compare it to a flowing current in a circuit, conventional current always opposes the flow of electrons in a circuit.

jun 2006
Q11> alpha particle moves in the same direction as the conventional current so following the rule your thumb should point towards the paper.

as the beta particle moves in the opposite direction then deflection is in the opposite direction.

nid404

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Re: Physics help
« Reply #16 on: May 06, 2009, 12:23:49 pm »
This explanation tells me that alpha moves out of paper and my textbook says the same but the mark scheme differs.(It says alpha moves into the paper)
I'm in a fix....seriously man...I hope I get it before my exam starts. Somebody plz help. Thanks for ur help anyways yac_belga. If you can explain in some other way plz do.

A diagram or a video may solve it. I know the left hand rule but I just don't understand the deflection.

Offline astarmathsandphysics

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Re: Physics help
« Reply #17 on: May 06, 2009, 12:29:11 pm »
try this

There is an excellent mnemonic, pioneered many years ago in Canada, which does away with the need for either of Fleming's complex rules. Imagine that electrons are eskimos, running through a forest. The fir trees look like arrows pointing up, and represent lines of force (ie a north pole is beneath the eskimos). As the eskimos run they always veer towards the left. That is the only rule needed.

Offline yinyang

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