A length of wire has a resistance of 10 ohms. What is the resistance of a wire of the same material three times as long and twice the cross-sectional area?

A. 30 ohms

B. 20 ohms

C. 15 ohms

D. 7 ohms

You can do it
  1. Permeability means
  2. Define as that pole which when placed in air from a similar and equal pole repels it with a force of…
  3. Magnetic field intensity is a ________ quantity.
  4. What is the unit of reluctance?
  5. The force of attraction or repulsion between two magnetic poles is directly proportional to their strengths.
  6. Under ordinary conditionsa a body is considered
  7. Which of the following is used by temporary magnets as the magnetic material?
  8. A group of magnetically aligned atoms is called
  9. The magnetic materials should have a large hysteresis loss for one of the following applications.
  10. A substance that attracts pieces iron
  11. The air space between poles of magnets
  12. Cobalt is an example of a ______ material.
  13. The quantity of magnetism retained by a magnetic material after withdrawal of the magnetizing force…
  14. What bond is formed when one or more electrons in the outermost energy orbit of an atom are transferred…
  15. Which of the following has the highest permeability?
  16. What is the other name for dielectric strength?
  17. Hysteresis is a phenomenon of _________ in a magnetic circuit.
  18. What principle states that each electron in an atom must have a different set of quantum numbers?
  19. The unit of flux density is
  20. Electron is a Greek word for
  21. The process by which an emf and hence current is generated or induced in a conductor when there is a…
  22. An alloy of 40 percent iron and 60 percent nickel.
  23. If two similar charges 1 coulomb each are placed 1 m apart in aira then the force of repulsion is
  24. A current if flowing east along a power line. If the earth's field is neglecteda the direction of the…
  25. Who demonstrated the theory of electromagnetic induction in 1831?
  26. When the relative permeability of a material is slightly more than 1a it is called ______ material.
  27. The force acting on a pole of 5 Wb is 25 N. What is the intensity of the magnetic field?
  28. A magnetic flux of 2.5 x10^4 Wb through an area of 5 x10^4 square meters results in
  29. The K shell or the first shell has how many permissible number of orbiting electrons?
  30. The B-H curve of ________ is not a straight line.