A capacitor is charged to a voltage V and then disconnected from the battery. If
Practice Questions
Q1
A capacitor is charged to a voltage V and then disconnected from the battery. If the distance between the plates is doubled, what happens to the voltage across the capacitor?
It doubles
It halves
It remains the same
It quadruples
Questions & Step-by-Step Solutions
A capacitor is charged to a voltage V and then disconnected from the battery. If the distance between the plates is doubled, what happens to the voltage across the capacitor?
Correct Answer: Voltage increases.
Step 1: Understand that a capacitor stores electrical energy and has two plates with a certain distance between them.
Step 2: When the capacitor is charged to a voltage V, it holds a certain amount of charge Q.
Step 3: The relationship between charge (Q), capacitance (C), and voltage (V) is given by the formula Q = C * V.
Step 4: When the capacitor is disconnected from the battery, the charge Q remains constant because no charge can flow in or out.
Step 5: The capacitance (C) of a capacitor is affected by the distance (d) between the plates. If the distance is doubled, the capacitance decreases.
Step 6: Since Q is constant and C decreases, the voltage V must increase to keep the equation Q = C * V balanced.
Step 7: Therefore, when the distance between the plates is doubled, the voltage across the capacitor increases.
Capacitance and Voltage Relationship – The relationship between capacitance (C), charge (Q), and voltage (V) in a capacitor, where Q = CV.
Effect of Plate Separation – How changing the distance between capacitor plates affects capacitance and voltage.
