1 / 29

Magnetism and Electromagnetic Induction

Magnet Basics. All Magnets have Poles which cannot be separated.Like poles _______, Opposite poles ______Magnetic Fields align N to S around a magnetThe Earth has a very large Magnetic Field. Magnet Basics. The direction of a magnetic field at any point in space is the direction indicated by the

dante
Download Presentation

Magnetism and Electromagnetic Induction

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

    1. Magnetism and Electromagnetic Induction Chapter 21 & 22

    2. Magnet Basics All Magnets have Poles which cannot be separated. Like poles _______, Opposite poles ______ Magnetic Fields align N to S around a magnet The Earth has a very large Magnetic Field

    3. Magnet Basics The direction of a magnetic field at any point in space is the direction indicated by the north pole of a small compass needle placed at that point. The magnetic field at any point is tangent to the magnetic field line at that point. (Same as electric fields!) Where would the fields be strongest? Weakest?

    4. Magnet Basics Electric currents produce magnetic fields The magnetic field is __________ if the wire is looped The shape of the magnetic field is ___________ circles.

    5. Magnet Basics When current in a wire is also in the presence of a magnetic field, the wire will __________ up or down. What law of Physics tells you that if a current carrying wire produces a force on a magnet, a magnet must produce a force on the current carrying wire?

    6. Check Your Neighbor… Why can iron be made to behave as a magnet while wood cannot? A strong magnet and a weak magnet attract each other. Which magnet exerts the stronger force? (Think back to Ch 4) Why will the magnetic field strength be further increased inside a current-carrying coil if a piece of iron is placed in the coil?

    7. Magnetic Fields – determining force Two conditions must be met for a charge to experience a magnetic force while in a magnetic field: The charge must be moving. The velocity of the moving charge must have a component that is perpendicular to the direction of the magnetic field

    8. Magnetic Fields – determining force Right hand rule #1: If the fingers of your right hand are pointed in the direction of the magnetic field (B), and the thumb points in the direction of the velocity (v) of the charge, the palm points in the direction of the force that is acting on a positive test charge.

    9. Magnetic Fields – determining force To calculate the magnitude of the magnetic field, we use: B = F / (qo(v sinT) Units are Tesla (T) = N·s/C·m

    10. Check your neighbor Why can a magnetic force perform no work?

    11. To work on now (at home if you don’t finish) Pg 659 – 662:CQ 1-4, Prob 1-7

    12. Where does the particle go? If we know a force is exerted, can we figure out the path of a moving charged particle in a magnetic field? First, let’s think conceptually… Now, lets see if we can arrive at an equation

    13. Where does the particle go? So, the path is circular The size of the radius is dependent on mass, velocity, charge and field intensity, given by: r = (mv) / (qB) The angle is 90, so the sine function = 1.

    14. Finding force on a current carrying wire. Recall the equation for finding force of a field: F = q B v sin? Since charges are moving, and moving takes time, lets add time to the equation and see what happens…

    15. Finding force on a current carrying wire. Did you come up with F = I l B sin? ? If not, here’s how…

More Related