Capacitors And Capacitance

Step 1: Concept
.
Step 2: Analysis
Capacitance depends on Geometry (A, d) and the Dielectric ( ).
Step 3: Conclusion
The type of metal used for the conducting plates does not affect the charge storage capacity.
Final Answer: (D)

Step 1: Properties
Argon is an inert noble gas.
Step 2: Application
In high-temperature metallurgical processes like welding, it is crucial to prevent the metal from reacting with oxygen or nitrogen.
Step 3: Conclusion
Argon provides a non-oxidising, inert atmosphere required for high-temperature welding.
Final Answer: (c)

Step 1: Understanding the circuit and the formula for charge.
The charge on a capacitor is given by the formula: where is the capacitance and is the potential difference across the capacitor.

Step 2: Determining the voltage across the capacitor.
- The total voltage provided by the cell is 2.5 V, and the internal resistance of the cell is 0.5 . - Using Ohm’s Law, the current in the circuit can be determined as: - The voltage across the capacitor is therefore the same as the voltage across the capacitor plates:

Step 3: Conclusion.
The charge on the capacitor is: Thus, the correct answer is (1).

Step 1: Understanding the Concept:
Soap bubble has two surfaces. Work done = .
Step 2: Detailed Explanation:
Initial surface area = .
Final radius = , so final area = .
Increase in area = .
Work done = .
Step 3: Final Answer:
Thus, work done = .

Concept:

Step 1: Work from 5V to 10V


Step 2: Work from 0 to 5V


Step 3: Ratio
Thus equivalent option: Conclusion:

Step 1: Understanding the Concept:
Initial charge: . Extra charge given = .
Step 2: Detailed Explanation:
Total charge on system: . For an isolated capacitor, effective charge producing potential difference: . .
Step 3: Final Answer:

Concept:
• Battery connected voltage remains constant
• Dielectric introduced capacitance increases

Step 1:Capacitance

Step 2:Charge

Step 3:Energy

Step 4:Potential difference Conclusion : (A)

Concept: For an isolated capacitor:
•Charge remains constant:
•Capacitance
•Voltage
•Electric field

Step 1: Initially , finally

Step 2: Since capacitor is already charged (isolated):

Step 3: Voltage relation:

Step 4: Electric field: