📚 Topic Summary
In this lab activity, we'll explore how inserting a dielectric material between the plates of a capacitor affects its ability to store charge. A capacitor stores electrical energy by accumulating charge on its plates. A dielectric is an insulating material that, when placed between the plates, increases the capacitor's capacitance (its ability to store charge). This happens because the dielectric material polarizes in response to the electric field, effectively reducing the electric field strength within the capacitor and allowing more charge to be stored at a given voltage.
Essentially, the presence of a dielectric allows a capacitor to hold more charge at the same voltage compared to when there is only air or a vacuum between the plates. We will investigate this relationship through practical experiments.
🧪 Part A: Vocabulary
Match the terms with their correct definitions:
| Term |
Definition |
| 1. Capacitance |
a. The insulating material placed between capacitor plates. |
| 2. Dielectric |
b. The ability of a capacitor to store electrical charge. |
| 3. Electric Field |
c. A device used to store electrical energy. |
| 4. Capacitor |
d. A region around a charged particle or object within which a force would be exerted on other charged particles or objects. |
| 5. Polarization |
e. The alignment of molecular dipoles in a material due to an external electric field. |
📝 Part B: Fill in the Blanks
A ________ is a device used to store electrical ________. When a ________ material is inserted between the plates of a capacitor, its ________ increases. This is because the dielectric reduces the ________ ________, allowing more charge to be stored at the same voltage.
🤔 Part C: Critical Thinking
Imagine you have two identical capacitors, one with air between its plates and one with a dielectric. If you charge both capacitors to the same voltage, which one will store more energy and why? Explain your answer using the formula for energy stored in a capacitor: $U = \frac{1}{2}CV^2$ where U is energy, C is capacitance, and V is voltage.