• Accueil
  • Science
  • Cite 2 uses of permanent magnets where electromagn...

Cite 2 uses of permanent magnets where electromagnets could not be used


  • Réponse publiée par: JUMAIRAHtheOTAKU


    an electro magnets is magnets that runs on electricty.Unlike ofpwrmanent magnet the strenth of electro magnet can be easily change by changing the amount of electric current tat flows through it.

  • Réponse publiée par: sicienth

    26. You see your face clearly if you look in a pool of still water. Which one of the following statements gives the best explanation for this observation?

    B. Regular reflection of light happens on the surface of still water

    27. What type of mirror do dentists usually use to see clearly the images of our teeth?

    C. Concave Mirror

    28. Where should the object be placed in front of a concave mirror to form a virtual and

    magnified image?

    C. Between the focus and the vertex

    29. Which of the following equipment could magnify far objects and appear clearer?

    C. Binoculars and telescope

    30. What optical instrument uses both lens and mirror?

    c. Microscope

    31. If a man wishes to use a plane mirror on a wall to view both his hands and his feet as he stands in front of the mirror the required length of the mirror is

    b. equal to one half the height of the man.

    32. When the image of an object is seen in a convex mirror, the image will

    b. Always be virtual

    33. When the image of an object is seen in a concave mirror, the image will

    c. Maybe either real or virtual

    34. Why are convex mirrors used on cars?

    a. Convex mirrors have a wider field of view

    35. You see the reflection of the clock without numbers in your plane mirror. The image

    formed by the hands of the clock shows the time of 3:30. What is the real time?

    b. 8:30

    36. Where should an object be placed in front of a concave mirror so that the image would

    have the same size as an object?

    b. At the center of the curvature

    37. What type of lens produces smaller and upright images?

    a. Concave lens

    38. are images that are formed by the intersection of real refracted rays.

    a. real images

    39. is an object that attracts certain materials such as iron.

    b. magnet

    40. Listed below are non-magnetic except

    d. iron

    41. If two magnets were in this order: NS NS they would?

    b. Attract

    42. What will happen if you strike an iron nail with a magnet?

    b. The nail will become magnetic

    43. Which of the following are ferromagnetic materials?

    d. All of these

    44. Early compasses were created with which of the following.

    d. Lodestone

    45. According to a Greek legend, who was the shepherd that first discovered the magnet?

    c. Megnes

    46. Who conceptualized the theory which states that inside a magnet there are small regions

    in which the magnetic direction of all atoms are a gned in the same directions?

    b Domain Theory

    47 The force that a magnet exerts on a certain material is called

    c. magnetic force

    48. What happens when two magnets with the same poles were brought closer to each

    a. The two magnets repel each other

    49. The strongest part of a magnet is/are

    c the poles

    50. What is the space or area around a magnet where the force is?

    c. magnetic field

    b. Magnetic field


Connaissez-vous la bonne réponse?
Cite 2 uses of permanent magnets where electromagnets could not be used...