28/03/2020 Magnetism and Electromagnetic Effects(Senior Class Physics Study by Topics) 28/03/2020 0Comments by Gate Academy Welcome to your Magnetism and Electromagnetic Effects(Senior Class Physics Study by Topics) NAME EMAIL PHONE NUMBER 1. An ac electromagnet Repels all permanent magnets. Either attracts or repels permanent magnets, depending on the polarity. Attracts only permanent magnets. Attracts pure, unmagnetized iron. 2. Which of the following can occur during a geomagnetic storm? The earth’s magnetic field is affected. More than one of the above can occur Electrical power transmission is disrupted. Charged particles stream out from the sun. 3. You can tell if an object is magnetic if the groupings of atoms: Are lined up in the same direction Are lined up in opposite directions Are scattered in all different directions 4. The ratio of intensity of magnetization to the magnetization force is known as Flux density Relative permeability None of the above Susceptibility 5. If a wire coil has 100 turns and carries 1.30 A of current, what is the magnetomotive force? 61.0 Gb 164 Gb 130 Gb 76.9 Gb 6. A magnet made of a material that keeps its magnetism is known as a Temporary magnet Permanent magnet Energizer bunny magnet Lifetime magnet 7. How can you make a magnet temporarily lose its magnetism? Both a & c By hitting it very hard By blowing on it By heating it 8. A magnetic hard disk is usually part of A computer. A tape recorder. An electromagnet A dc motor. 9. A straight long wire carries an electric current to the right. The current is placed in a uniform magnetic field directed into the page. What is the direction of the magnetic force on the current? To the bottom of the page. To the top of the page. Left Right 10. If a wire coil has 10 turns and carries 500 mA of current, what is the magnetomotive force? 5.0 At 0.02 At 50 At 5000 At 11. An object is not magnetized if: The groupings of atoms are lined up The groupings of atoms are scattered The groupings of atoms are in the same direction 12. A bar magnet is divided in two pieces. Which of the following statements is true about the force between the broken pieces if they face each other with a small separation? There is an electric attractive force between the broken pieces. There is a magnetic repulsive force between the broken pieces. There is an electric repulsive force between the broken pieces. There is a magnetic attractive force between the broken pieces. 13. What substance is attracted to a magnet? Lead Water Silver Iron 14. Temporary magnets are used in Loudspeakers Generators Motors All of the above 15. Which of the following is expected to have the maximum permeability? Ebonite Brass Zinc Copper 16. Ampere-turn is the unit of magneto-motive force (mmf). True False 17. A ferromagnetic material is: A material that shows no magnetic effects A material that shows strong magnetic effects A material that shows weak magnetic effects 18. An advantage of a magnetic disk, compared with magnetic tape, for data storage and retrieval is that Disks are less susceptible to magnetic fields. Disks look better. A disk lasts longer. Data can be stored and retrieved more quickly with disks than with tapes. 19. The presence of a magnetic field can always be attributed to Diamagnetic materials The north geomagnetic pole Motion of electric charge carriers. Ferromagnetic materials. 20. The smallest particle of an element is known as an: Atom Proton Neutron Electron 21. A particle that does not carry an electrical charge is a: Proton Neutron Electron Atom 22. The magnetic flux around a straight, current-carrying wire Consists of straight lines parallel to the wire. Does not vary in strength with distance from the wire. Is strongest near the wire. Gets stronger with increasing distance from the wire. 23. A straight long wire carries an electric current to the top of the page. The current is placed in a uniform magnetic field directed out the page. What is the direction of the magnetic force on the current? To the bottom of the page Right Left. To the top of the page 24. A vertical wire carries an electric current out of the page. What is the direction of the magnetic field at point P located to the west from the wire? East. North. West. South. 25. A tiny, negatively charged particle that usually exists in the outer region of an atom is called a: Neutron Electron Proton Nucleus 1 out of 25 Time is Up! Time's up