الأمتحان

The opposite figure shows four conductors of uniform cross-sections made of the same materials but with different dimensions, so their correct arrangement in an ascending orderaccording to their electrical resistances is …….

Which combination of the following resistors gives an equivalent resistance of value R ?

Four equal resistors are connected together as in the following figures, so the correct arrangement of the figures from the least equivalent resistance to the highest one is ………..

By applying Kirchhoff’s first law at the point (x), So ……….

In the shown electric circuit, the equivalent resistance between points a, b equals ………..

In the opposite electric circuit, when the key (K) is closed, the voltmeter reading becomes ………….

In the electric circuit shown, the electric current intensity (I) equals …………

Two wires are made of the same material, the diameter of the first wire is 3 times the diameter of the second wire and the resistance of the second wire is 4 times the resistance of the first wire, so the length of the second wire is ………… the length of the first wire.

Four equal resistors are connected together as in the following figures, which figure gives the least equivalent resistance?

In the electric shown circuit, we can apply Kirchhoff’s second law to the closed path (adcba) as follows ……

In the opposite electric circuit, when the key (K) is closed, the ammeter reading becomes ………

Arrange the figures according to their equivalent resistance ascendingly given that the resistors are identical.

From the opposite electric circuit, the correct equation is ……….

In the shown closed electric circuit: When the value of resistance S is increased ……..

In the shown three electric circuits (1), (2) and (3). Which one from the following relations is correct?

A current of I intensity passes through a conductor of l length and cross-sectional area A, when the battery is changed with a different one, the current passing through the same conductor becomes 3I, so the cross-sectional area of the conductor becomes ………….

The figure illustrates a wire in the form of semi-circles connected together and connected to a cell. Which of these semi-circles has the least magnetic flux density at its center?

The figure illustrates two current-carrying conductors (x) and (y). A current of intensity I passes through conductor (x) while a current of intensity (2 A) passes through conductor (y). Then, the current (I) that causes the magnetic flux density at point M to be zero is …………

A sensitive galvanometer of resistance 15Ω was connected to different shunts to convert it into an ammeter of different range in each time. Which of the following figures represents the ammeter that has the maximum range scale?

A long straight wire carries electric current of intensity I as in the figure, which one from the following expressions relates correctly the magnetic flux density (B) that is produced due to the current through the wire at two of the points x,y and z that lie in the same plane of the wire?

Four metallic circular rings of different radii carry equal current intensities as in the figure, so the smallest magnetic flux density is generated at the center (C) of ring ……………

In the shown figure, the resultant magnetic flux density at point 𝐏 due to the two electric currents that are passing through the two wires (𝐱) and (𝐲) is 𝑩𝒕, so if the direction of the passing current through wire (𝐱) is reversed while keeping the current of (y) as it is, the resultant magnetic flux density at point 𝐏 becomes …………

A current-carrying straight wire is put tangent to the outer ring of two concentric rings that carry electric currents in the same direction. If all of them are in the same plane and carry currents that have intensity I as shown in the figure, the resulting magnetic flux density at the common center (𝐦) due to the three currents equals ………

Two straight wires 1,2 are in the same plane perpendicular to the plane of the page, a current of I intensity passes through each of them in the same direction, so if a magnetic needle is placed at the mid-point between them as in the figure, the north pole of the needle is expected to ……………

The graph represents the relation between the magnetic flux density (B) at a point due to passing a current in the straight wire and the current intensity (I) for three straight wires ( 𝒙,𝒚 and 𝐳), so this point is ……..

Two concentric rings both carry electric current I at the same direction as shown in the figure, producing magnetic field of flux density B at the common center (O). If the direction of the passing current through one ring only is reversed keeping the other current as it is, so the resultant magnetic flux density at (O) becomes ………