Physical Science 6.8b - Magnetic Force on Moving Charge

Рет қаралды 89,234

Күн бұрын

From the Physical Science course by Derek Owens. An explanation of the force exerted by a magnetic field on a moving charge. Distance learning classes are available at www.derekowens.com

Пікірлер: 51

@EugenMihailescu 11 жыл бұрын

The right hand rule can be memorized as a mnemonic: FIB (force-current-field) where F is your thumb, I is your index finger and B is your middle finger. Note that F =thumb is up, I=index is pointing forward and B=middle is perperndicular on your index (or on your palm). The left hand rule is also useful and can be memorize like FBI. These mnemonics help me to remember these useful rules.

@viru200-h2t 2 ай бұрын

Its FBI not FIB. Please be more careful when commenting advice like this

@dalenassar9152 5 жыл бұрын

GREAT VIDEO! However at about the 5:00 mark, you overlooked a very important concept that separates the concept of gravity vs E-field. You forget to mention the -direction / polarity- of the charge in an E-field vs the (non-polorized) mass in a G-field.

@taimai3364 7 жыл бұрын

I truly appreciate your work and would love to learn more about superconductors!

@derekowens 13 жыл бұрын

@AceFrolic720 If you are thinking of the positive charge flowing, then you should use the Right Hand Rule. Positive charge flowing one way is mathematically the same as negative charge flowing the opposite way. You should get the same result for your force vector either way.

@derekowens 14 жыл бұрын

@freerider10000 The actual direction is a source of constant confusion because there are two ways to think of it. If you imagine the current to be positive charge flowing, what we call conventional current, then you use the right hand rule. If you imagine it to be negative charge flowing in the other direction, what we call electron flow, then you use the left hand rule. Positive charge flowing in one direction is mathematically equivalent to negative charge flowing in the other direction.

@MrShadmanAziz 12 жыл бұрын

I absolutely agree with you. I'm doing A level physics and we use the Left hand rule for motors.

@tripmeter235 12 жыл бұрын

John Fleming lived in the years between the 19th and 20th centuries. So it must be remembered that he would have been using "conventional current", ie flowing from the positive of his supply. Nowadays the tendancy is towards using electron flow as a current and the direction is from the negative of the supply. Regardless, as the tutor here says, they interpret as the same thing. Clasp a bar in both hands with your thumbs pointing towards each other then your fingers curl in same direction.

@geirmarius 11 жыл бұрын

Woha thanks. This is extremely helpful for my physics exam this Friday.

@salemraffa2263 10 жыл бұрын

thank you so very much im in the 9th grade at a german school ( you know how uptight they are ) and i didnt understand alot there but thanks to your videos i now do. your awesome bro thanks

@freerider10000 14 жыл бұрын

Hi, I'm just wondering why you use the Right hand rule to determine the direction of a magnetic force instead of Flemings Left hand motor rule? From my understanding the Flemings Left hand motor rule says the First finger points along the Field direction (From N to S). The seCond finger is the Current direction (from + to -) and then the Thumb gives the direction of the Thrust (or the Force). (Note I'm from the UK and only use Right hand Rule for generators and stick to conventional current)

@DisturbedV7 13 жыл бұрын

I dont understand the bit about the magnet and using the right hand rule, are your fingers not wrapped around when the actual field lines are straight?

@mephatboi 13 жыл бұрын

how did u know to point ur thumb downwards (not upwards) in the 1st instance of the moving particle and upwards (not downwards) when it traveled in the opposite direction?

@amrinfathima7036 8 жыл бұрын

Can u explain what is the difference between Fleming's right and left hand rule?why do we need them and what do you mean by emf?

@Adaeze611 14 жыл бұрын

How do you know where the field lines point? out or in. Like the earth example, they point in...and the second one they point out...? how do I know this?

@derekowens 14 жыл бұрын

@12345Anee I think I need to make a video on Flemings motor rule. I have to find some free time first, and that's pretty scarce these days...

@xXCatalystic37Xx 14 жыл бұрын

Why didn't you you show at the very end what direction the force would be on the charged particle? I was JUST about to confirm using the right hand rule what direction it would be. I think it would be into the screen at that orientation, being that the tangent of the magnetic field would be pointed up towards the top of the screen, the velocity is adjacent towards the left of the screen, and therefore using right hand rule the force would be into the screen.

@Cyno7 13 жыл бұрын

i'm confused, do all charged particles hav a magnetic field around them; so in your last example, the charge q. so are there 2 magnetic fields interacting in that situation. what i'm trying to understand is determining the force etc when we have an interaction of magnetic fields produced by a permanent magnet and an electromagnet (i.e. from current in wire)

@algol291 9 жыл бұрын

At the median point of a magnets force, the particle flows in the opposite direction? But, when electricity is applied to a large wire, the magnetic flow will always be constant? Is that right?

@unnatikumar9074 9 жыл бұрын

i love your videos! thanks a lot ;)

@balochan1 13 жыл бұрын

are the yellow lines representing the force or the magnetic field?

@algol291 9 жыл бұрын

Does a magnetic field spiral from a starting point to an end point, or do magnets produce separate lines of force, individual from one another?

@derekowens 14 жыл бұрын

@zsj382387304 No, it's not uniform. The field lines would be curved. Similar to the field around an electric dipole.

@calicoesblue4703 Жыл бұрын

Great Video brotha😎👍

@moezart94 12 жыл бұрын

Hi Mr.Owens. I was wondering if the reason of a moving charge going downwards is because it produces a magnetic field that repels with the North pole. Please tell me if I'm right or wrong, thanks.

@aidasaad97 9 жыл бұрын

Thank you. Well explained.

@jozozo100 14 жыл бұрын

what about a charge in a magnetic field but not moving? Does anything happen then?

@AneeqaChowdhury 14 жыл бұрын

@derekowens but Sir, that guy is asking about Flemings Left hand motor rule.....!!!! even i m also wondering why you use the Right hand rule to determine the direction of a magnetic force instead of Flemings Left hand motor rule?

@fatmagomaa103 9 жыл бұрын

this was great for me to understand what happen in materials and how things work but i was searching at first (before i saw this great episodes) about the difference between B & H magnetic field , could you please explain it for me ?

@kabascoolr 9 жыл бұрын

+Fatma Goma'a If I understand your equation correctly, the only difference between them is a constant mu or the permeability. It's just like the relationship between E and D, the electric field and the electric field density. mu is the material property of the stuff you're in.

@AneeqaChowdhury 14 жыл бұрын

@derekowens @derekowens but Sir, that guy is asking about Flemings Left hand motor rule.....!!!! even i m also wondering why you use the Right hand rule to determine the direction of a magnetic force instead of Flemings Left hand motor rule?

@Underdisc 12 жыл бұрын

I would like to see a video on how to find the radius of a gravity well or the radius of an electric field. If you could please publish one or direct me to one, I would be very happy! =D

@MoonLight-ub1vs 10 жыл бұрын

Do magnetic forces always move

@mephatboi 13 жыл бұрын

@mephatboi nvm, u answered it in the next video (i.e. fingers must curl in the direction of the south pole)! thx...

@AneeqaChowdhury 14 жыл бұрын

but Sir, that guy is asking about Flemings Left hand motor rule.....!!!!(freerider10000 )) even i m also wondering why you use the Right hand rule to determine the direction of a magnetic force instead of Flemings Left hand motor rule?

@JillYva 9 жыл бұрын

Where does left hand rule work cause I'm soo confused ThuMb Motion/First finger Force/seCond finger Current wait is Motion Force? Yes? Even so I'm still confused af

@JillYva 9 жыл бұрын

I got my head around some parts but it cleared a lot out tbh but I'm just really slow in the end I learnt Yh that's how it is deal with it

@seanki98 8 жыл бұрын

This is based on the cross product F=qv cross B correct?

@derekowens 8 жыл бұрын

Yes, exactly. This course is at an introductory level, though, with most of the math being first year algebra or earlier, so we don't get into the vector math in this course. You are correct, though.