Chapter - 13
Magnetic Effects of Electric Current
( āĻŦৈāĻĻ্āϝুāϤিāĻ āĻĒ্ā§°āĻŦাāĻšā§° āĻুāĻŽ্āĻŦāĻীāϝ় āĻĒ্ā§°āĻাā§ą )
EXERCISES :-
( āĻŦ্āϝাāϝ়াāĻŽ :- )
1. Which of the following correctly describes the magnetic field near a long straight wire?
( āύিāĻŽ্āύāϞিāĻিāϤ āĻোāύāĻোā§ąে āĻĻীāĻāϞ āĻĒোāύ āϤাঁā§°ā§° āĻāĻā§°āϤ āĻুāĻŽ্āĻŦāĻীāϝ় āĻ্āώেāϤ্ā§°āĻো āϏāĻ িāĻāĻাā§ąে āĻŦā§°্āĻŖāύা āĻā§°ে? )
(a) The field consists of straight lines perpendicular to the wire.
( āĻ্āώেāϤ্ā§°āĻāύāϤ āϤাঁā§°ā§° āϞāĻŽ্āĻŦāĻাā§ąে āϏ⧰āϞ ā§°েāĻা āĻĨাāĻে। )
(b) The field consists of straight lines parallel to the wire.
( āĻ্āώেāϤ্ā§°āĻāύāϤ āϤাঁā§°ā§° āϏāĻŽাāύ্āϤ⧰াāϞāĻাā§ąে āϏ⧰āϞ ā§°েāĻা āĻĨাāĻে। )
(c) The field consists of radial lines originating from the wire.
( āĻ্āώেāϤ্ā§°āĻāύāϤ āϤাঁā§°ā§° āĻĒā§°া āĻāĻĻ্āĻā§ą āĻšোā§ąা ā§°েāĻĄিāϝ়েāϞ ā§°েāĻা āĻĨাāĻে। )
(d) The field consists of concentric circles centred on the wire.
( āĻ্āώেāϤ্ā§°āĻāύāϤ āϤাঁā§°ā§° āĻāĻĒā§°āϤ āĻেāύ্āĻĻ্ā§°ীāĻূāϤ āϏāĻŽāĻেāύ্āĻĻ্ā§°িāĻ āĻŦৃāϤ্āϤ āĻĨাāĻে। )
Answer:-
2. The phenomenon of electromagnetic induction is
( āĻŦিāĻĻ্āϝুāϤāĻুāĻŽ্āĻŦāĻীāϝ় āĻ āύ্āϤ⧰্āĻুāĻ্āϤিā§° āĻĒā§°িāĻāĻāύা āĻšৈāĻে )
(a) the process of charging a body.
( āĻļā§°ীā§° āĻāĻা āĻাā§°্āĻ āĻā§°াā§° āĻĒ্ā§°āĻ্ā§°িāϝ়া। )
(b) the process of generating magnetic field due to a current passing through a coil.
( āĻুāĻŖ্āĻĄāϞীāĻāĻাā§° āĻŽাāĻেā§°ে āĻĒাā§° āĻšৈ āϝোā§ąা āĻŦিāĻĻ্āϝুāϤ⧰ āĻĢāϞāϤ āĻুāĻŽ্āĻŦāĻীāϝ় āĻ্āώেāϤ্ā§° āϏৃāώ্āĻি āĻā§°াā§° āĻĒ্ā§°āĻ্ā§°িāϝ়া। )
(c) producing induced current in a coil due to relative motion between a magnet and the coil.
( āĻুāĻŽ্āĻŦāĻ āĻā§°ু āĻুāĻŖ্āĻĄāϞীā§° āĻŽাāĻāϤ āĻāĻĒেāĻ্āώিāĻ āĻāϤিā§° āĻŦাāĻŦে āĻুāĻŖ্āĻĄāϞীāĻāĻাāϤ āĻĒ্ā§°েā§°িāϤ āĻŦিāĻĻ্āϝুā§ āĻĒ্ā§°āϏ্āϤুāϤ āĻā§°া। )
(d) the process of rotating a coil of an electric motor.
( āĻŦৈāĻĻ্āϝুāϤিāĻ āĻŽāĻā§°ā§° āĻুāĻŖ্āĻĄāϞী āĻূā§°াā§° āĻĒ্ā§°āĻ্ā§°িāϝ়া। )
Answer:-
3. The device used for producing electric current is called a
( āĻŦৈāĻĻ্āϝুāϤিāĻ āĻĒ্ā§°āĻŦাāĻš āĻĒ্ā§°āϏ্āϤুāϤ āĻā§°াā§° āĻŦাāĻŦে āĻŦ্āĻ¯ā§ąāĻšৃāϤ āĻĄিāĻাāĻāĻāĻোāĻ āĻ āĻŦুāϞি āĻোā§ąা āĻšāϝ় )
(a) generator.
( āĻেāύেā§°েāĻā§°। )
(b) galvanometer.
( āĻাāϞāĻাāύোāĻŽিāĻাā§°। )
(c)ammeter.
( āĻāĻŽāĻŽিāĻাā§°। )
(d) motor.
( āĻŽāĻā§°। )
Answer:-
4. The essential difference between an AC generator and a DC generator is that
(āĻāĻি āĻেāύেā§°েāĻā§° āĻā§°ু āĻĄিāĻি āĻেāύেā§°েāĻā§°ā§° āĻŽাāĻā§° āĻ āϤ্āϝাā§ąāĻļ্āϝāĻীāϝ় āĻĒাā§°্āĻĨāĻ্āϝ āĻšৈāĻে āϝে)
(a) AC generator has an electromagnet while a DC generator has permanent magnet.
( āĻāĻি āĻেāύেā§°েāĻā§°āϤ āĻāϞেāĻ্āĻ্ā§°āĻŽেāĻāύেāĻ āĻĨাāĻে āĻāύāĻšাāϤে āĻĄিāĻি āĻেāύেā§°েāĻā§°ā§° āϏ্āĻĨাāϝ়ী āĻুāĻŽ্āĻŦāĻ āĻĨাāĻে। )
(b) DC generator will generate a higher voltage.
( āĻĄিāĻি āĻেāύেā§°েāĻā§°ে āĻāĻ্āĻāϤ⧰ āĻāϞ্āĻেāĻ āϏৃāώ্āĻি āĻā§°িāĻŦ। )
(c) AC generator will generate a higher voltage.
( āĻāĻি āĻেāύেā§°েāĻā§°ে āĻāĻ্āĻāϤ⧰ āĻāϞ্āĻেāĻ āϏৃāώ্āĻি āĻā§°িāĻŦ। )
(d) AC generator has slip rings while the DC generator has a commutator.
( āĻāĻি āĻেāύেā§°েāĻā§°āϤ āϏ্āϞিāĻĒ ā§°িং āĻāĻে āĻāύāĻšাāϤে āĻĄিāĻি āĻেāύেā§°েāĻā§°āϤ āĻāĻা āĻāĻŽিāĻāĻেāĻā§° āĻāĻে। )
Answer:-
5. At the time of short circuit, the current in the circuit
āĻļ্āĻŦā§°্āĻ āĻাā§°্āĻিāĻā§° āϏāĻŽāϝ়āϤ, āĻŦā§°্āϤāύীāϤ āĻŦিāĻĻ্āϝুāϤ )
(a) reduces substantially.
( āϝāĻĨেāώ্āĻ āĻĒā§°িāĻŽাāĻŖে āĻš্ā§°াāϏ āĻšāϝ়। )
(b) does not change.
( āϏāϞāύি āύāĻšāϝ়। )
(c) increases heavily.
( āϝāĻĨেāώ্āĻ āĻŦৃāĻĻ্āϧি āĻšāϝ়। )
(d) vary continuously.
( āύিā§°āύ্āϤ⧰ āĻাā§ąে āĻĒৃāĻĨāĻ āĻšāϝ়। )
Answer:-
6. State whether the following statements are true or false.
( āύিāĻŽ্āύāϞিāĻিāϤ āĻŽāύ্āϤāĻŦ্āϝāĻŦোā§° āϏঁāĻা āύে āĻŽিāĻা āϏেāϝ়া āĻāĻঁāĻ। )
(a) An electric motor converts mechanical energy into electrical energy.
( āĻāĻা āĻŦৈāĻĻ্āϝুāϤিāĻ āĻŽāĻā§°ে āϝাāύ্āϤ্ā§°িāĻ āĻļāĻ্āϤিāĻ āĻŦৈāĻĻ্āϝুāϤিāĻ āĻļāĻ্āϤিāϞৈ ā§°ূāĻĒাāύ্āϤ⧰ āĻā§°ে। )
(b) An electric generator works on the principle of electromagnetic induction.
( āĻŦৈāĻĻ্āϝুāϤিāĻ āĻেāύেā§°েāĻā§°ে āĻŦিāĻĻ্āϝুāϤāĻুāĻŽ্āĻŦāĻীāϝ় āĻ āύ্āϤ⧰্āĻুāĻ্āϤিā§° āϏিāĻĻ্āϧাāύ্āϤāϤ āĻাāĻŽ āĻā§°ে। )
(c) The field at the centre of a long circular coil carrying current will be parallel straight lines.
(āĻŦিāĻĻ্āϝুā§ āĻāĻĸ়িāĻā§ąা āĻĻীāĻāϞ āĻŦৃāϤ্āϤাāĻাā§° āĻুāĻŖ্āĻĄāϞীā§° āĻেāύ্āĻĻ্ā§°āϤ āĻĨāĻা āĻĒāĻĨাā§°āĻāύ āϏāĻŽাāύ্āϤ⧰াāϞ āϏ⧰āϞ ā§°েāĻা āĻš'āĻŦ। )
(d) A wire with a green insulation is usually the live wire of an electric supply.
( āϏেāĻāĻীāϝ়া āĻāύāĻুāϞেāĻāύ āĻĨāĻা āϤাঁā§° āĻšৈāĻে āϏাāϧাā§°āĻŖāϤে āĻŦৈāĻĻ্āϝুāϤিāĻ āϝোāĻাāύ⧰ āĻীā§ąāύ্āϤ āϤাঁā§°। )
Answer:-
7. List two methods of producing magnetic fields.
( āĻুāĻŽ্āĻŦāĻীāϝ় āĻ্āώেāϤ্ā§° āĻĒ্ā§°āϏ্āϤুāϤ āĻā§°াā§° āĻĻুāĻা āĻĒāĻĻ্āϧāϤি āϤাāϞিāĻাāĻুāĻ্āϤ āĻā§°āĻ। )
Answer:-
8. How does a solenoid behave like a magnet? Can you determine the north and south poles of a current-carrying solenoid with the help of a bar magnet? Explain.
( āĻোāϞেāύāĻāĻĄে āĻুāĻŽ্āĻŦāĻā§° āĻĻā§°ে āĻেāύে āĻāĻā§°āĻŖ āĻā§°ে? āĻāĻĒুāύি āĻŦাā§° āĻুāĻŽ্āĻŦāĻā§° āϏāĻšাāϝ়āϤ āĻŦিāĻĻ্āϝুā§ āĻāĻĸ়িāĻā§ąা āĻোāϞেāύāĻāĻĄā§° āĻāϤ্āϤ⧰ āĻā§°ু āĻĻāĻ্āώিāĻŖ āĻŽেā§°ু āύিā§°্āϧাā§°āĻŖ āĻā§°িāĻŦ āĻĒাā§°িāĻŦāύে? āĻŦ্āϝাāĻ্āϝা āĻā§°āĻ। )
Answer:-
9. When is the force experienced by a current-carrying conductor placed in a magnetic field largest?
( āĻুāĻŽ্āĻŦāĻীāϝ় āĻ্āώেāϤ্ā§°āϤ āϏ⧰্āĻŦāĻŦৃāĻšā§ āϏ্āĻĨাāύāϤ ā§°āĻা āĻŦā§°্āϤāĻŽাāύ āĻāĻĸ়িāĻā§ąা āĻĒā§°িāĻŦাāĻšীā§° āĻĻ্āĻŦাā§°া āĻেāϤিāϝ়া āĻŦāϞ āĻ āύুāĻā§ą āĻā§°া āĻšāϝ়? )
Answer:-
10. Imagine that you are sitting in a chamber with your back to one wall. An electron beam, moving horizontally from back wall towards the front wall, is deflected by a strong magnetic field to your right side. What is the direction of magnetic field?
( āĻāϞ্āĻĒāύা āĻā§°āĻ āϝে āĻāĻĒুāύি āĻāĻāύ āĻŦেā§°āϤ āĻĒিāĻ ি āĻĻি āĻāĻা āĻেāĻŽ্āĻŦাā§°āϤ āĻŦāĻšি āĻāĻে। āĻĒিāĻāĻĢাāϞ⧰ āĻŦেā§°ā§° āĻĒā§°া āϏāύ্āĻŽুāĻā§° āĻŦেā§°ā§° āĻĢাāϞে āĻĒāĻĨাāϞিāĻৈ āĻāϞাāĻāϞ āĻā§°া āĻāϞেāĻ্āĻ্ā§°āύ āĻŦীāĻŽ āĻāĻা āĻļāĻ্āϤিāĻļাāϞী āĻুāĻŽ্āĻŦāĻীāϝ় āĻ্āώেāϤ্ā§°ā§° āĻĻ্āĻŦাā§°া āĻāĻĒোāύাā§° āϏোঁāĻĢাāϞে āĻŦিāĻ্āϝুāϤ āĻšāϝ়। āĻুāĻŽ্āĻŦāĻীāϝ় āĻ্āώেāϤ্ā§°ā§° āĻĻিāĻļ āĻি? )
Answer:-
11. Draw a labelled diagram of an electric motor. Explain its principle and working. What is the function of a split ring in an electric motor?
( āĻŦৈāĻĻ্āϝুāϤিāĻ āĻŽāĻā§°ā§° āϞেāĻŦেāϞ āϝুāĻ্āϤ āύāĻ্āϏা āĻঁāĻāĻ। āĻāϝ়াā§° āύীāϤি āĻā§°ু āĻাāĻŽ āĻŦ্āϝাāĻ্āϝা āĻā§°āĻ। āĻŦৈāĻĻ্āϝুāϤিāĻ āĻŽāĻā§°āϤ āϏ্āĻĒ্āϞিāĻ ā§°িং āĻāĻাā§° āĻাāĻŽ āĻি? )
Answer:-
12. Name some devices in which electric motors are used.
( āĻŦৈāĻĻ্āϝুāϤিāĻ āĻŽāĻā§° āĻŦ্āĻ¯ā§ąāĻšাā§° āĻā§°া āĻিāĻুāĻŽাāύ āĻĄিāĻাāĻāĻā§° āύাāĻŽ āĻĻিāϝ়āĻ। )
Answer:-
13. A coil of insulated copper wire is connected to a galvanometer. What will happen if a bar magnet is (i) pushed into the coil, (ii) withdrawn from inside the coil, (iii) held stationary inside the coil?
( āĻāύāĻুāϞেāĻেāĻĄ āϤাāĻŽā§° āϤাঁā§°ā§° āĻুāĻŖ্āĻĄāϞী āĻāĻা āĻাāϞāĻাāύোāĻŽিāĻাā§°ā§° āϏৈāϤে āϏংāϝোāĻিāϤ āĻšāϝ়। āϝāĻĻি āĻŦাā§° āĻুāĻŽ্āĻŦāĻ āĻāĻা āĻুāĻŖ্āĻĄāϞীāϤ āĻ েāϞি āĻĻিāϝ়া āĻšāϝ়, (āĻāĻāĻāĻ) āĻুāĻŖ্āĻĄāϞীā§° āĻিāϤ⧰⧰ āĻĒā§°া āĻĒ্ā§°āϤ্āϝাāĻšাā§° āĻā§°া āĻšāϝ়, (āϤৃāϤীāϝ়) āĻুāĻŖ্āĻĄāϞীā§° āĻিāϤ⧰āϤ āϏ্āĻĨিā§° āĻšৈ āĻĨাāĻে āϤেāύেāĻš'āϞে āĻি āĻš'āĻŦ? )
Answer;-
14. Two circular coils A and B are placed closed to each other. If the current in the coil A is changed, will some current be induced in the coil B? Give reason.
( āĻĻুāĻা āĻŦৃāϤ্āϤাāĻাā§° āĻুāĻŖ্āĻĄāϞী āĻ āĻā§°ু āĻŦি āĻāĻāύে āϏিāĻāύ⧰ āĻŦাāĻŦে āĻŦāύ্āϧ āĻā§°া āĻšāϝ়। āϝāĻĻি āĻুāĻŖ্āĻĄāϞী āĻ-āϤ āĻĨāĻা āĻŦিāĻĻ্āϝুāϤ āĻĒā§°িā§ąā§°্āϤāύ āĻā§°া āĻšāϝ়, āĻুāĻŖ্āĻĄāϞী āĻŦি-āϤ āĻিāĻু āĻŦিāĻĻ্āϝুā§ āĻĒ্ā§°েā§°িāϤ āĻš'āĻŦ āύেāĻি? āĻাā§°āĻŖ āĻĻিāϝ়āĻ। )
Answer:-
15. State the rule to determine the direction of a (i) magnetic field produced around a straight conductor-carrying current, (ii) force experienced by a current-carrying straight conductor placed in a magnetic field which is perpendicular to it, and (iii) current induced in a coil due to its rotation in a magnetic field.
( āĻāĻা āĻĒোāύ āĻĒā§°িāĻŦাāĻšী āĻāĻĸ়িāĻā§ąা āĻĒ্ā§°āĻŦাāĻšā§° āĻাā§°িāĻāĻĢাāϞে āĻā§āĻĒāύ্āύ āĻšোā§ąা (āĻ) āĻুāĻŽ্āĻŦāĻীāϝ় āĻ্āώেāϤ্ā§°ā§° āĻĻিāĻļ āύিā§°্āϧাā§°āĻŖ āĻā§°াā§° āύিāϝ়āĻŽ āĻো āĻāĻঁāĻ, (āĻ) āĻুāĻŽ্āĻŦāĻীāϝ় āĻ্āώেāϤ্ā§°āϤ ā§°āĻা āĻāĻ āĻŦā§°্āϤāĻŽাāύ-āĻāĻĸ়িāĻā§ąা āĻĒোāύ āĻĒā§°িāĻŦাāĻšীā§° āĻĻ্āĻŦাā§°া āĻ āύুāĻā§ą āĻā§°া, āϝি āĻāϝ়াā§° āϞāĻŽ্āĻŦ, āĻā§°ু (āĻ) āĻুāĻŽ্āĻŦāĻীāϝ় āĻ্āώেāϤ্ā§°āϤ āĻāϝ়াā§° āĻূā§°্āĻŖāύ⧰ āĻĢāϞāϤ āĻুāĻŖ্āĻĄāϞীāĻāĻাāϤ āĻĒ্ā§°েā§°িāϤ āĻšোā§ąা āĻŦিāĻĻ্āϝুāϤ। )
Answer:-
16. Explain the underlying principle and working of an electric generator by drawing a labelled diagram. What is the function of brushes?
( āϞেāĻŦেāϞ āϝুāĻ্āϤ āύāĻ্āϏা āĻāĻāύ āĻঁāĻি āĻŦৈāĻĻ্āϝুāϤিāĻ āĻেāύেā§°েāĻā§°ā§° āĻ āύ্āϤ⧰্āύিāĻšিāϤ āύীāϤি āĻā§°ু āĻাāĻŽ āĻŦ্āϝাāĻ্āϝা āĻā§°āĻ। āĻŦ্ā§°াāĻā§° āĻাāĻŽ āĻি? )
Answer:-
17. When does an electric short circuit occur?
( āĻŦৈāĻĻ্āϝুāϤিāĻ āĻļ্āĻŦā§°্āĻ āĻাā§°্āĻিāĻ āĻেāϤিāϝ়া āĻšāϝ়? )
Answer:-
18. What is the function of an earth wire? Why is it necessary to earth metallic appliances?
(āĻĒৃāĻĨিā§ąীā§° āϤাঁā§°ā§° āĻাā§°্āϝ্āϝ āĻি? āϧাāĻ¤ā§ąীāϝ় āϏঁāĻুāϞিāĻŦোā§° āĻĒৃāĻĨিā§ąীāϤ āĻĨāĻাāĻো āĻিāϝ় āĻĒ্ā§°āϝ়োāĻāύীāϝ়?)
Answer:-
Post ID ;DABP004563