Capacitor 1st July

Which of the following statement is true?

• Electrostatic force is a conservative force.

• Potential at a point is the work done per unit charge in bringing a charge from any point to infinity

• Electrostatic force is non-conservative

• Potential is the product of charge and work.

Equipotential surfaces

• are closer in regions of large electric fields compared to regions of lower electric fields.

• will be more crowded near sharp edges of a conductor.

• will always be equally spaced.

• both (a) and (b) are correct.

A proton moves 10 cm on a path in the direction of a uniform electric field of strength 3.0 N/C. How much work is done on the proton by the electrical field?

• 4.8 x 10^-20 J

• -4.8 x 10^-20 J

• .6 x 10^-20 J

• zero

A 9.0-V battery is connected between two parallel metal plates 4.0 mm apart. What is the magnitude of the electric field between the plates?

• 2.3 x 10³ N/C

• 9.0 N/C

• 2.3 N/C

• 0.75 x 10^-6 N/C

A parallel-plate capacitor has a capacitance of 20 µF. What potential difference across the plates is required to store 7.2 x 10^-4 C on this capacitor?

• 36 V

• 2.2 x 10^-2 V

• 1.4 x 10^-8 V

• 68 V

Increasing the separation of the two charged parallel plates of a capacitor, which are disconnected from a battery, will produce what effect on the capacitor?

• increase charge

• decrease charge

• increase capacitance

• decrease capacitance

Three capacitors of 1.0 µF, 1.5 µF, and 2.0 µF are connected in series. Find the combined capacitance.

• 4.5 µF

• 4.0 µF

• 2.2 µF

• 0.46 µF

If three 4.0 µF capacitors are connected in parallel, what is the combined capacitance?

• 12 µF

• 0.75 µF

• 8.0 µF

• 0.46 µF

Two capacitors with C_A greater than C_B and are connected in series with a battery. Which of the following is true?

• There is more charge stored on C_A.

• There is more charge stored on C_B.

• There is the same charge stored on each capacitor.

• There is the same potential difference across both capacitors.

What is the equivalent capacitance between points a and b? All capacitors are 1.0 µF.

• 4.0 µF

• 17 µF

• 0.6 µF

• 0.25 µF