- “Kirchhoff’s” law is preferred over Ohm’s law. Why?
- Can we apply Kirchhoff’s law to both a.c. and D.C.?
- Kirchhoff’s laws are related to certain conservation laws. Explain?
- “Wheatstone bridge method of determination of resistance is considered to be more accurate than the voltmeter-ammeter method”. Why?
- When the Wheatstone bridge most sensitive?
- Wheatstone bride is not suitable for measuring very low and very high resistances. Why?
- A meter bridge wire is called a slide wire bridge. Why?
- It is better to get null deflection at the middle of the wire in a meter bridge. Why?
- What is meant by end correction for the meter bridge? How it can be reduced?
- What is potentiometer? What is its principle?
- What is potential gradient? What is the significance of it? Why it should be small for more accurate measurement?
- The potentiometer wire should be long and of uniform thickness. Why?
- The sensitivity of potentiometer wire can be increased by increasing its length. But we are usually satisfied with 10 m long wire. Why?
- Which instrument will you prefer to measure the emf of a cell: a high resistance voltmeter or potentiometer? Explain?
- Why are Meter Bridge and P. O. Box so named?
- While using post office box it is instructed that the cell key should tapped first and then the galvanometer key. Why?
- Why should the cross section of wire be uniform?
- What happens if the galvanometer and cell are interchanged at balanced point of a wheatstone’s bridge? Would the galvanometer show any deflection?
- What advantage is there in measuring resistance by using wheatstone bridge?
- A potentiometer is equivalent to a voltmeter of infinite resistance. Explain?
- Can the potentiometer wire be of copper? Explain?
- How would you convince that the principle of measurement of resistance of wire by Meter Bridge is based on Wheatstone bridge principle? Explain?
- If the length of wire be doubled what will be the effect on the position of null deflection in a potentiometer?
- What is the advantage of using a greater length of potentiometer wire?
- In Wheatstone bridge method why do we break the galvanometer circuit first and then the battery circuit?
- Why the connection between resistors in Wheatstone bridge or Meter Bridge are made of thick copper wires?
- Can Meter Bridge be used for measuring very low resistances?
- Why the jockey should not be pressed against the potentiometer wire?
- The emf of the driver cell should always be greater than emf of the cell to be measured. Why?
- Can you interchange the positions of the battery in the auxiliary circuit and cell whose emf is to b determined in potentiometer circuit diagram?
- Why the current should not be passed through the potentiometer wire for long time?
- Is it possible that there is no potential between the plates of the cell? If yes, under what conditions?
Heat and temperature Short questions: 1. Distinguish between heat and temperature? 2. Distinguish between heat and work? 3. When two bodies A and B are brought in contact, heat flows from body B to A. Which is at higher temperature? 4. Why is mercury used commonly as a thermometric substance? Give two reasons. 5. What is thermal equilibrium? Can two object not in contact ever be in thermal equillibrium? 6. State Zeroth law of thermodynamics? Define temperature on the basis of Zeroth law of thermodynamics? 7. Why two objects in thermal contact come in thermal equilibrium? 8. Which physical quantity determines the direction of flow of heat? 9. ...