Capacitance and Dielectrics Concepts

What factors determine the capacitance of a long cylindrical capacitor?

• Its length and the radii of its inner and outer cylinders.

• The type of material between the cylinders.

• The amount of charge stored on its plates.

• The voltage applied across its plates.

How does the capacitance of a spherical capacitor change if the outer radius (b) increases while the inner radius (a) remains constant?

• It increases.

• It decreases.

• It remains the same.

• It depends on the charge.

When a battery charges a capacitor, what happens to the energy?

• Energy is created within the capacitor.

• Energy is transferred from the battery and stored in the capacitor's electric field.

• Energy is converted into heat and lost.

• Energy is destroyed as charge moves between plates.

A 2.00 µF capacitor is connected to a 300.0 V battery. What is the energy stored in the capacitor?

• 0.0900 J

• 0.0450 J

• 0.180 J

• 0.000900 J

Two capacitors, 2.00 µF and 4.00 µF, are connected in parallel to a 300.0 V battery. What is the total energy stored in the capacitors?

• 0.090 J

• 0.18 J

• 0.27 J

• 0.36 J

What are the standard units for energy density in an electric field?

• Joules per meter (J/m)

• Joules per square meter (J/m²)

• Joules per cubic meter (J/m³)

• Joules per Coulomb (J/C)

What happens to the capacitance of a parallel-plate capacitor when an insulating material (dielectric) is slipped between its plates, assuming the charge on the plates remains constant?

• The capacitance decreases.

• The capacitance increases.

• The capacitance remains the same.

• The capacitance becomes zero.

What does the dielectric constant (κ) of a material represent?

• The material's ability to conduct electricity.

• The ratio of the electric field in vacuum to the electric field in the material.

• The material's resistance to electric current.

• The amount of charge stored per unit volume.

What is the primary effect of inserting a dielectric material between the plates of a capacitor?

• It decreases the capacitance

• It increases the voltage

• It increases the capacitance

• It decreases the charge

Which material has the highest dielectric constant among the options provided?

• Teflon

• Paper

• Pure water (20°C)

• Strontium titanate