Section A: Magnetic Field & Field Lines
- Define Magnetic Field. Is it a scalar or vector quantity?
- List two important properties of magnetic field lines.
- Why do two magnetic field lines never intersect each other?
- Draw a diagram showing the pattern of magnetic field lines around a bar magnet.
- State the direction of magnetic field lines (i) inside and (ii) outside a bar magnet.
- Where is the magnetic field strongest in a plot of field lines?
- What is the function of a magnetic compass?
- Describe Oersted's experiment briefly.
- Draw the pattern of magnetic field lines due to a straight current carrying conductor.
- State the rule used to find the direction of magnetic field associated with a current carrying
conductor.
- How does the strength of magnetic field produced by a straight conductor depend on (i) current, (ii)
distance from conductor?
- Draw the magnetic field lines due to a circular loop carrying current.
- How can you identify the north and south poles of a current carrying loop? (Clock Face Rule).
- How does a uniform magnetic field look like diagrammatically?
- What happens to a compass needle when placed near a current carrying wire?
Section B: Electromagnets & Solenoids
- What is a Solenoid?
- Draw the pattern of magnetic field lines produced by a current carrying solenoid.
- List two similarities between a solenoid and a bar magnet.
- Mention three ways to increase the strength of magnetic field inside a solenoid.
- What is an Electromagnet?
- Distinguish between a permanent magnet and an electromagnet. (Two points).
- Why is soft iron used as the core of an electromagnet?
- Why is steel not suitable for making electromagnets?
- State the polarity of the face of a solenoid if current flows in the clockwise direction.
- State the polarity of the face of a solenoid if current flows in the anti-clockwise direction.
- Give two practical applications of electromagnets.
- What happens to the magnetic field of an electromagnet if the current is switched off?
- Can we use copper as the core of a solenoid to make an electromagnet? Explain.
- Draw a circuit diagram to make an electromagnet using a soft iron nail.
- Compare the field inside a long solenoid with that of a bar magnet.
Section C: Force on Conductor & EMI
- Under what condition does a current carrying conductor experience a force in a magnetic field?
- State Fleming's Left Hand Rule.
- When is the force experienced by a current carrying conductor (i) Maximum, (ii) Minimum?
- Name the device which uses current carrying conductors and magnetic fields to produce mechanical
motion.
- What is the principle of an Electric Motor?
- What is the function of the Split Ring (Commutator) in an electric motor?
- What is the function of Carbon Brushes in an electric motor?
- Define Electromagnetic Induction (EMI).
- State Fleming's Right Hand Rule.
- Name the device used to convert mechanical energy into electrical energy.
- Differentiate between the functions of Fleming's Left Hand Rule and Fleming's Right Hand Rule.
- List two methods of inducing current in a coil.
- What is the difference between AC and DC?
- Draw a graph showing Direct Current and Alternating Current with time.
- What is a Galvanometer? How is it different from an Ammeter?
Section D: Domestic Electric Circuits
- What are the three types of wires used in domestic circuits? Mention their insulation colors.
- What is the function of the Earth Wire? Why is it important?
- What is the potential difference between Live and Neutral wires in India?
- What is Short-Circuiting? How does it happen?
- What is Overloading? Brief two causes.
- What is an Electric Fuse? On what principle does it work?
- How does a fuse wire protect electrical appliances?
- Why is a fuse wire made of a material with low melting point?
- A fuse is rated 5A. What does this mean?
- Why are domestic appliances connected in parallel? Give two reasons.
- Calculate the fuse rating for an appliance of 1.5 kW working on 220 V supply.
- What is the frequency of AC used in India? How does it differ from DC frequency?
- Why is it dangerous to touch a live wire?
- What precautions should be taken to avoid overloading in domestic circuits?
- Why should the switch always be connected in the live wire?