CBSE Class 10 Science Chapter 13 Magnetic Effects Of Electric Current Very Short Answer Questions
Question 1. Draw a diagram to represent a uniform magnetic field in a given region.
Answer:
Question 2. Why is earthing important for electrical appliances?
Answer: It saves the person operating the device from electric shock and also saves the device from excessive current due to some fault.
Question 3. What is the capacity of a fuse commonly used in domestic electrical fitting?
Answer: Fuses of capacity 5 A or 15 A are commonly used in domestic electrical fittings.
Read and Learn More CBSE Class 10 Science Very Short Answer Questions
Question 4. What will you do if you see a person coming in contact with a live wire?
Answer: Such a person should be provided with an insulated support like wood, plastic, or rubber to disconnect the person from the wire.
Question 5. What does the closeness of field lines in a magnetic field signify?
Answer: It indicates the strength of the magnetic field in the region.
Question 6. Name the alloy which is mainly used for making permanent magnets.
Answer: Alnico (an alloy of aluminum, nickel, cobalt, and iron).
Question 7. An alternating electric current has a frequency of 50Hz. How many times does it change its direction in one second?
Answer: Since AC changes its direction twice in a cycle, it will change its direction 100 times (50 x 2) in one second as its frequency is 50 Hz.
Question 8. Mention the voltage and frequency of current that we receive at our house.
Answer:
- Voltage-220 V
- Frequency-50 Hz
Question 9. State the direction ofthe magnetic field inside the bar magnet.
Answer: From south to north pole.
Question 10. Name the factors on which force acting on a current-carrying conductor depends.
Answer:
- Strength of the magnetic field.
- The current through the conductor
- The length of the conductor.
Question 11. What is meant by electromagnetic induction?
Answer: It is the phenomenon of producing an electric current in a conductor by changing the magnetic field through the conductor.
Question 12. Name the rule used to find the direction of force on a current-carrying conductor.
Answer: Fleming’s left-hand rule
Question 13. What is the shape of magnetic field lines around a straight current-carrying conductor?
Answer: Concentric circles.
Question 14. Name the type of current:
- Used in household supply
- Given by cell
Answer: Alternating Current (AC) and Direct Current (DC)
Question 15. What type of core is used to make an electromagnet?
Answer: Soft, iron
Question 16. Mention the special feature regarding the shape of magnetic field lines.
Answer: They are closed curves.
Question 17. How is a fuse connected in an electric circuit?
Answer: It is connected in series in the circuit.
Question 18. What is short-circuiting1?
Answer: The coming together of the live and neutral wire is called short-circuiting.
Question 19. Why is the metallic body of electrical devices connected to the earth wire?
Answer: This is because it provides a low-resistance conducting path for the current to flow to The earth. Thereby protecting the user from a severe electric shock.
Question 20. Write any one method to induce a current in a coil.
Answer: By moving a magnet towards a coil.
Question 21. Suggest one way of discriminating between a wire carrying current and a wire carrying no current.
Answer: Bring a magnetic needle near the wire. A current-carrying wire will produce a deflection in the needle whereas a wire without current will not.
Question 22. How can you magnetize a piece of magnetic material?
Answer: We can do so by placing it inside a current-carrying solenoid.
Question 23. How is the circuit overloaded?
Answer: By connecting too many devices to it.
Question 24. Mention the angle between a current-carrying conductor and a magnetic field for which the force experienced by this current-carrying conductor placed in a magnetic field is the largest.
Answer: The angle is 90°.
Question 25. How does a current-carrying solenoid behave?
Answer: It behaves like a bar magnet.
Question 26. On which effect of electricity does the fuse work?
Answer: Heating effect of current.
Question 27. Why is a fuse usually made of tin-copper alloy?
Answer: A fuse is usually made of tin or tin-copper alloy because it has a low melting point.
Question 28. What is a solenoid?
Answer: A Solenoid is a coil of many turns of wire wrapped in the shape of a cylinder.
Question 29. What does the direction of thumb indicate in the right-hand thumb rule?
Answer: The thumb indicates the direction of current in the straight conductor held by curled Angers.
Question 30. How is the magnetic field produced in a solenoid used?
Answer: It is used to magnetize a soft iron piece to form an electromagnet.
Question 31. Why does a compass needle get deflected when brought near a bar magnet?
Answer: The magnetic field of the magnet exerts force on both the poles of the compass needle. The forces experienced by the two poles are equal and opposite. These two forces form a couple which deflects the compass needle.
Question 32. Draw magnetic field lines around a bar magnet. (PBQ)
Answer: A complete pattern of the magnetic field lines around a bar magnet is shown in the
figure
Question 33. List two methods of producing magnetic fields.
Answer: Permanent magnets and electromagnets.