First quiz

Unlike poles repel each other.

• True

• False

The material used in loudspeakers are  …. magnetic materials.

• soft

• hard

The materials used in the core of motors are  …. magnetic materials.

• SOFT

• HARD

The geographic north of earth corresponds to the magnetic south pole.

• TRUE

• FALSE

The magnetic filed lines of the earth are from the geographic ….. pole to the geographic ….. pole.

• south - north

• north - south

The magnetic force affecting a charge (0.25 mC) moves with a speed of 40 m/s in direction makes angle 30º to magnetic field 0.1 T is ……

• 0.5 N

• 0.0005 N

• 0.0000005 N

• 0.5 T

Find the direction of the magnetic force on an electron moving through the magnetic fields in the opposite figure

• to outside

• to inside

The magnetic field affects both the stationary and moving charges charges.

• TRUE

• FALSE

1 G ……. 10000 T

• is less than

• equals to

• is higher than

The magnitude of magnetic force on a wire with 100 m length and carries a current of 20 A from north to south is …… N. If the magnetic field of Earth has a magnitude of 0.5x10^-4 T.

• 0.1

• 0.05

• None of these values