3rd year 7 chapters

A potential difference of 12 V is applied between the terminals of a conductor to move 6.25 × 10¹⁸ electrons through a cross -section of this conductor within two seconds, then the resistance of the conductor is ................?

The opposite figure shows a conducting solid where each two opposite faces of the cuboid can be connected between the terminals of an electric source and the paths (1) , (2) , and (3) are the probable pathways of electric currents through the conductor, in which of these paths the electric current faces the highest resistance ?

• Path (1)

• Path (2)

• Path (3)

• All paths have the same resistance

In the opposite circuit , the ratio (R₁/R₂) is ................?

• 3/2

• 3/1

• 4/1

• 4/3

In the opposite electric circuit , if you know that the electric potential of the point connected to the Earth is zero .............?

• A

• B

• C

• D

In the opposite circuit, if the internal resistance of the battery is 1/4 R then the Voltmeter reading equals .............?

• 2/3 V_B

• 5/4 V_B

• 1/5 V_B

• 4/5 V_B

In the opposite electric circuit, the total resistance of the circuit equals ...........?

• 20.31°

• 10.53°

• 13.9°

• 15.52°

The opposite figure shows a circular ring and a straight wire which is placed at position x in the same plane of the ring where both carry electric currents of intensity I , so the resultant magnetic flux density at the center of the ring c is B . If the wire is moved to position y the magnetic flux density at point c becomes ...........?

• 2 B

• B

• 0.73 B

• 1.38 B

In the opposite figure, two identical solenoids , each of them carries an electric current, are placed near to each other where their axes are parallel, so the net magnetic field due to them at point x is directed ..............?

• Into the page

• Out of the page

• Upwards

• Downwards

The type of the mutual magnetic force between two current-carrying parallel wires depends on ...............?

• The direction of the current in each of them

• The intensity of the current in each of them

• The distance between them

• Their lengths