Physics Practice Test – Current Electricity and Electric Charges

A wire, 1.0 m long and with cross-sectional area 2.0 x 10^-7 m² has a resistance of 0.1Ω. Calculate the electrical conductivity of the wire.

A. 2.0 x 10⁷Ω^-1m^-1      B. 5.0 x 10⁷Ω^-1m^-1     C. 2.0 x 10⁸Ω^-1m^-1      D. 5.0 x 10⁸Ω^-1m^-1

The quantity of electric charge stored in a capacitor is measured in ______

A. farad    B. ampere    C. coulomb    D. volt

Which of the following factors does not affect the capacitance of a parallel plate capacitor?

A. Area of the plates
B. Nature of the surface of the plates
C. Distance of separation between the plates
D. Nature of the insulating material between the plates

The equivalent capacitance of a 3μF capacitor and a 6 μF capacitor connected in parallel is ______

A. 2.0 μF     B. 3.0 μF     C. 4.5 μF     D. 9.0μF

An electric lamp rated 120 W is used on a 240 V_rms, calculate the resistance of its filament.

A. 480 Ω     B. 360 Ω     C. 60 Ω     D. 2 Ω