2182

Physics Magnetism,Magnetic Effects Of Current Level: High School

The magnetic characteristics of a core material are shown in the figure at “click here”. What change in magnetizing force is required to reserve the direction of the magnetic field from saturation in the positive direction to saturation in the negative direction ?

a) 110 At/m

b) 140 At/m

c) 180 At/m

d) 220 At/m




2181

Physics Magnetism,Magnetic Effects Of Current Level: High School

The magnetic characteristics of a core material are shown in the figure at “click here”. What is the change in magnetizing force is required to decrease the flux density of the magnetic material from saturation in the positive direction to zero ?

a) 88 At/m

b) 110 At/m

c) 132 At/m

d) None of the above




2180

Physics Magnetism,Magnetic Effects Of Current Level: High School

Hysteresis Curve

The magnetic characteristics of a core material are shown in the figure at “click here”. What is the magnitude of the coercive force of the core material ?

a) 12 At/m

b) 22 At/m

c) 28 At/m

d) 35 At/m




2179

Physics Magnetism,Magnetic Effects Of Current Level: High School

The magnetic characteristics of a core material are shown in the figure at “click here” . which one of the following could be an approximate relative permeability of the material ?

a) 13000

b) 40000

c) 51000

d) 76000




2178

Physics Magnetism,Magnetic Effects Of Current Level: High School

The mks unit for energy density is the ?

a) weber per square meter.

b) weber-ampere-turn per square meter.

c) ampere-turn per cubic meter.

d) joule per cubic meter.




2177

Physics Magnetism,Magnetic Effects Of Current Level: High School

All ferromagnetic materials have nonlinear magnetic characteristics.

a) True

b) False

True



2176

Physics Magnetism,Magnetic Effects Of Current Level: High School

A core material has a relative permeability of 150000 . A magnetizing force is applied to the core and produces a flux density of 1.1 Wb/m^2 .If the magnetic path is 34.3 m long , what is the magnetomotive force to the core ? (Assume no air gap, and convert inches to meters)

a) 5.09 At

b) 15.9 At

c) 200 At

d) 226 At




2175

Physics Magnetism,Magnetic Effects Of Current Level: High School

A core material has a relative permeability of 150000 . A magnetizing force is applied to the core and produces a flux density of 1.1 Wb/m^2 . What is the value of the magnetizing force ?

a) 3.77 At/m

b) 5.84 At/m

c) 18.3 At/m

d) 23.4 At/m




2174

Physics Magnetism,Magnetic Effects Of Current Level: High School

Magnetizing force (magnetic field strength) and magnetomotive force are identical quantities .

a) True

b) False

False



2173

Physics Magnetism,Magnetic Effects Of Current Level: High School

A certain core material has an actual permeability of 4.40 x 10^-2 H/m. What is the relative permeability of the material ?

a) 35000

b) 176000

c) 140000

d) 552000




2172

Physics Magnetism,Magnetic Effects Of Current Level: High School

The mks unit of magnetizing force is the ?

a) ampere-turn per meter.

b) gausss

c) oersted

d) weber per square meter

a) ampere-turn per meter.



2171

Physics Magnetism,Magnetic Effects Of Current Level: High School

Which type of magnetic material would you choose to use as a shield for a meter movement ? The shield is to short-circuit the flux around the movement.

a) Paramagnetic

b) Diamagnetic

c) Ferromagnetic

c) Ferromagnetic



2170

Physics Magnetism,Magnetic Effects Of Current Level: High School

A core of magnetic material is of constant cross-sectional area and has a short air gap . A magnetomotive force is applied , and it produces a flux in the series magnetic path but does not saturate the core . The flux density of the magnetic path.

a) is always the same in the air gap as in the iron .

b) will probably be somewhat greater in the air gap than in the iron .

c) will probably be somewhat less in the air gap .

d) will probably be much less in the air gap .

c) will probably be somewhat less in the air gap .



2169

Physics Magnetism,Magnetic Effects Of Current Level: High School

In the mks system the correct unit for flux density is ?

1) Webers

2) Webers/meter^2

3) maxwells / centimeter^2

4) none of the above

2) Webers/meter^2



2168

Physics Magnetism,Magnetic Effects Of Current Level: High School

In the mks system what is the unit for permeability ?

1) flux/meter

2) henrys/meter

3) ampere-turns/m^3

4) ampere-turns/Weber.

2) henrys/meter

Displaying 121-135 of 200 results.