Electric Field vs Magnetic Field
Date: 2015-10-07; view: 490.
| Electric field | Magnetic field | |
| Nature | ||
| Units | ||
| Its force | ||
| Movement in electromagnetic field |
1. It is created around moving electric charge and magnets.
2. It is perpendicular to the magnetic field.
3. It is proportional to the electric charge.
4. Newton per coulomb, volts per meter.
5. It is proportional to charge and speed of electric charge.
6. Gauss or tesla.
7. It is created around electric charge .
8. It is perpendicular to the electric field.
Exercise 79. Using the text ‘Magnetic Fields and Forces' complete the table with the information about differences between the electric and magnetic forces.
| Electric force | Magnetic force |
| 1. | 1. |
| 2. | 2. |
| 3. | 3. |
Exercise 80. Fill in the gaps with the words below.
south electric field cancel north
magnet magnetic field spinning opposite
magnetic force electric charge electron lines
tiny greater same
The direction of the magnetic field outside a magnet is from the ________ to the _________ pole.The space around a magnet, in which a ____________ is exerted, is filled with a magnetic field. The shape of the field is revealed by magnetic field ______ that spread out from the north pole, curve around the _________, and return to the south pole. Where the magnetic field lines are closer together, the field strength is _________ than where the lines are farther apart. A magnetic field is produced by the motion of __________. Just as an electric charge is surrounded by an ________, a moving electric charge is surrounded by a _________. Both the orbital motion and the spinning motion of every ________ in an atom produce magnetic fields. Every ________ electron is a ______ magnet. Multiple electrons spinning in the ________ direction make a stronger magnet, but electrons spinning in _________ directions work against one another. Their magnetic fields ________.
Exercise 81. Circle the letter of each statement about electric and magnetic fields that is correct.
a) An electric field is a field of force, surrounding a charged particle, while a magnetic field is a field of force surrounding a permanent magnet, or a moving charged particle.
b) The strength of an electric field is expressed in Tesla or Gauss, while a magnetic field strength is expressed in Newtons per Coulomb.
c) Electric and magnetic fields oscillate at right angles to one another.
d) Where the magnetic field lines are close together, the field strength is great.
e) Where the magnetic field lines are far apart, the field strength is weak.
f) Where the magnetic field lines are parallel, the field strength is zero.
g) The field strength around a magnetic pole does not vary with distance.
h) The magnetic field cannot exert a force on an uncharged particle.
i) The magnetic field can only exert a force on a charged particle that is moving.
j) The magnetic force always acts parallel to the direction of motion of the moving charged particle.
Exercise 82. Circle the correct answer.
1. The north-pole end of a bar magnet is held near a positively charged piece of plastic. Is the plastic…?
a) attracted b) repelled c) unaffected by the magnet
2. A charged particle moves with velocity v in a magnetic field B. The magnetic force on the particle is a maximum when v is …
a) zero b) parallel to B c) perpendicular to B
3. An electron moves in the plane of this paper toward the top of the page. A magnetic field is also in the plane of the page and directed toward the right. The direction of the magnetic force on the electron is… a) toward the top of the page d) toward the right edge of the page
b) toward the bottom of the page e) upward out of the page
c) toward the left edge of the page f) downward into the page
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| MAGNETIC FIELDS AND FORCES | | | Language work. Words often confused. |