Ferromagnetism in Physics : āĻĒāĻĻāĻžā§°ā§āĻĨ āĻŦāĻŋāĻā§āĻāĻžāĻ¨āĻ¤ Ferromagnetism
Ferromagnetism in Physics : āĻĒāĻĻāĻžā§°ā§āĻĨ āĻŦāĻŋāĻā§āĻāĻžāĻ¨āĻ¤ Ferromagnetism
Ferromagnetism is the strong magnetism shown by materials like iron, cobalt, and nickel. In these materials, tiny atomic magnets align in the same direction, producing a strong permanent magnet. Ferromagnetism āĻšā§āĻā§ āĻ˛ā§āĻšāĻž (Iron), āĻ’āĻŦāĻ˛ā§āĻ (Cobalt) āĻā§°ā§ āĻ¨āĻŋāĻā§āĻ˛ (Nickel)ā§° āĻĻā§°ā§ āĻĒāĻĻāĻžā§°ā§āĻĨāĻ¤ āĻĻā§āĻāĻž āĻĒā§ā§ąāĻž āĻļāĻā§āĻ¤āĻŋāĻļāĻžāĻ˛ā§ āĻā§āĻŽā§āĻŦāĻāĻ¤ā§āĻŦāĨ¤ āĻāĻ āĻĒāĻĻāĻžā§°ā§āĻĨāĻ¸āĻŽā§āĻšāĻ¤ āĻ āĻŖā§āĻ¸āĻŽā§āĻš āĻāĻā§ āĻĻāĻŋāĻļāĻ¤ āĻ¸āĻā§āĻāĻŋāĻ¤ āĻšāĻ¯āĻŧ āĻā§°ā§ āĻļāĻā§āĻ¤āĻŋāĻļāĻžāĻ˛ā§ āĻ¸ā§āĻĨāĻžāĻ¯āĻŧā§ āĻā§āĻŽā§āĻŦāĻ āĻ¸ā§āĻˇā§āĻāĻŋ āĻā§°ā§āĨ¤
Examples / āĻāĻĻāĻžāĻšā§°āĻŖ : i. Iron (āĻ˛ā§āĻšāĻž) ii. Cobalt (āĻ’āĻŦāĻ˛ā§āĻ) iii. Nickel (āĻ¨āĻŋāĻā§āĻ˛)
- Ferromagnetic materials can become permanent magnets. (Ferromagnetic āĻĒāĻĻāĻžā§°ā§āĻĨ āĻ¸ā§āĻĨāĻžāĻ¯āĻŧā§ āĻā§āĻŽā§āĻŦāĻ āĻš’āĻŦ āĻĒāĻžā§°ā§āĨ¤)
- These materials are strongly attracted by magnets. (āĻāĻ āĻĒāĻĻāĻžā§°ā§āĻĨāĻ¸āĻŽā§āĻš āĻā§āĻŽā§āĻŦāĻā§° āĻĻā§āĻŦāĻžā§°āĻž āĻŦā§āĻāĻŋ āĻāĻā§°ā§āĻˇāĻŋāĻ¤ āĻšāĻ¯āĻŧāĨ¤)
Science Behind Permanent Magnets (āĻ¸ā§āĻĨāĻžāĻ¯āĻŧā§ āĻā§āĻŽā§āĻŦāĻā§° āĻŦāĻŋāĻā§āĻāĻžāĻ¨)
Inside ferromagnetic materials, groups of atoms called magnetic domains point in the same direction. This alignment creates a strong magnetic field. Ferromagnetic āĻĒāĻĻāĻžā§°ā§āĻĨā§° āĻāĻŋāĻ¤ā§°āĻ¤ magnetic domains āĻ¨āĻžāĻŽā§° āĻ āĻŖā§āĻ¸āĻŽā§āĻš āĻāĻā§ āĻĻāĻŋāĻļāĻ¤ āĻ¸āĻā§āĻāĻŋāĻ¤ āĻĨāĻžāĻā§āĨ¤ āĻāĻ āĻ¸āĻā§āĻāĻžāĻ āĻļāĻā§āĻ¤āĻŋāĻļāĻžāĻ˛ā§ āĻā§āĻŽā§āĻŦāĻā§āĻ¯āĻŧ āĻā§āĻˇā§āĻ¤ā§ā§° āĻ¸ā§āĻˇā§āĻāĻŋ āĻā§°ā§āĨ¤
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MCQ
1. Ferromagnetism is found in —. Ferromagnetism — āĻ¤ āĻĻā§āĻāĻž āĻ¯āĻžāĻ¯āĻŧāĨ¤
(a) Wood | (b) Plastic | (c) Iron | (d) Glass
Ans: (c) Iron
Explanation: Iron is a ferromagnetic material. āĻŦā§āĻ¯āĻžāĻā§āĻ¯āĻž: āĻ˛ā§āĻšāĻž āĻāĻāĻž ferromagnetic āĻĒāĻĻāĻžā§°ā§āĻĨāĨ¤
2. Which of the following is a ferromagnetic material ? āĻ¤āĻ˛ā§° āĻā§āĻ¨āĻā§ ferromagnetic āĻĒāĻĻāĻžā§°ā§āĻĨ ?
(a) Copper | (b) Nickel | (c) Aluminium | (d) Silver
Ans: (b) Nickel
Explanation: Nickel shows strong magnetic properties. āĻŦā§āĻ¯āĻžāĻā§āĻ¯āĻž: Nickel-āĻ āĻļāĻā§āĻ¤āĻŋāĻļāĻžāĻ˛ā§ āĻā§āĻŽā§āĻŦāĻā§āĻ¯āĻŧ āĻā§āĻŖ āĻĻā§āĻā§ā§ąāĻžāĻ¯āĻŧāĨ¤
3. Ferromagnetic substances are strongly attracted by —
Ferromagnetic āĻĒāĻĻāĻžā§°ā§āĻĨāĻ¸āĻŽā§āĻš āĻļāĻā§āĻ¤āĻŋāĻļāĻžāĻ˛ā§āĻāĻžā§ąā§ — āĻĻā§āĻŦāĻžā§°āĻž āĻāĻā§°ā§āĻˇāĻŋāĻ¤ āĻšāĻ¯āĻŧāĨ¤
(a) water | (b) heat | (c) magnets | (d) light
Ans: (c) magnets
Explanation: Ferromagnetic materials are strongly attracted by magnets. āĻŦā§āĻ¯āĻžāĻā§āĻ¯āĻž: Ferromagnetic āĻĒāĻĻāĻžā§°ā§āĻĨ āĻā§āĻŽā§āĻŦāĻā§° āĻĻā§āĻŦāĻžā§°āĻž āĻ āĻ§āĻŋāĻ āĻāĻā§°ā§āĻˇāĻŋāĻ¤ āĻšāĻ¯āĻŧāĨ¤
4. Which of the following can become a permanent magnet ? āĻ¤āĻ˛ā§° āĻā§āĻ¨āĻā§ āĻ¸ā§āĻĨāĻžāĻ¯āĻŧā§ āĻā§āĻŽā§āĻŦāĻ āĻš’āĻŦ āĻĒāĻžā§°ā§ ?
(a) Iron | (b) Paper | (c) Rubber | (d) Wood
Ans: (a) Iron
Explanation: Iron can retain magnetism for a long time. āĻŦā§āĻ¯āĻžāĻā§āĻ¯āĻž: āĻ˛ā§āĻšāĻžāĻ āĻŦāĻšā§ āĻ¸āĻŽāĻ¯āĻŧ āĻ§ā§°āĻŋ āĻā§āĻŽā§āĻŦāĻāĻ¤ā§āĻŦ āĻ§ā§°āĻŋ ā§°āĻžāĻāĻŋāĻŦ āĻĒāĻžā§°ā§āĨ¤
5. Ferromagnetism occurs due to alignment of —. — ā§° āĻ¸āĻā§āĻāĻžā§° āĻŦāĻžāĻŦā§ ferromagnetism āĻāĻā§āĨ¤
(a) molecules | (b) domains | (c) liquids | (d) electrons only
Ans: (b) domains
Explanation: Magnetic domains align in one direction to produce strong magnetism. āĻŦā§āĻ¯āĻžāĻā§āĻ¯āĻž: Magnetic domains āĻāĻā§ āĻĻāĻŋāĻļāĻ¤ āĻ¸āĻā§āĻāĻŋāĻ¤ āĻšā§ā§ąāĻžā§° āĻĢāĻ˛āĻ¤ āĻļāĻā§āĻ¤āĻŋāĻļāĻžāĻ˛ā§ āĻā§āĻŽā§āĻŦāĻāĻ¤ā§āĻŦ āĻā§āĻĒāĻ¨ā§āĻ¨ āĻšāĻ¯āĻŧāĨ¤
6. Which metal is NOT ferromagnetic ? āĻā§āĻ¨ āĻ§āĻžāĻ¤ā§ ferromagnetic āĻ¨āĻšāĻ¯āĻŧ ?
(a) Iron | (b) Cobalt | (c) Nickel | (d) Copper
Ans: (d) Copper
Explanation: Copper does not show ferromagnetism. āĻŦā§āĻ¯āĻžāĻā§āĻ¯āĻž: Copper-āĻ ferromagnetism āĻ¨ā§āĻĻā§āĻā§ā§ąāĻžāĻ¯āĻŧāĨ¤
7. Ferromagnetism is related to —. Ferromagnetism — ā§° āĻ¸ā§āĻ¤ā§ āĻāĻĄāĻŧāĻŋāĻ¤āĨ¤
(a) electricity | (b) heat | (c) magnetism | (d) sound
Ans:(c) magnetism
Explanation: Ferromagnetism is a magnetic property of materials. āĻŦā§āĻ¯āĻžāĻā§āĻ¯āĻž: Ferromagnetism āĻšā§āĻā§ āĻĒāĻĻāĻžā§°ā§āĻĨā§° āĻā§āĻŽā§āĻŦāĻā§āĻ¯āĻŧ āĻā§āĻŖāĨ¤
8. Which scientist is associated with magnetism studies ? āĻā§āĻ¨ āĻŦāĻŋāĻā§āĻāĻžāĻ¨ā§ āĻā§āĻŽā§āĻŦāĻāĻ¤ā§āĻŦ āĻ āĻ§ā§āĻ¯āĻ¯āĻŧāĻ¨ā§° āĻ¸ā§āĻ¤ā§ āĻāĻĄāĻŧāĻŋāĻ¤ ?
(a) Newton | (b) Faraday | (c) Darwin | (d) Edison
Ans: (b) Faraday
Explanation: Michael Faraday made important contributions to magnetism. āĻŦā§āĻ¯āĻžāĻā§āĻ¯āĻž: Michael Faraday-āĻ āĻā§āĻŽā§āĻŦāĻāĻ¤ā§āĻŦ āĻŦāĻŋāĻˇāĻ¯āĻŧāĻ¤ āĻā§ā§°ā§āĻ¤ā§āĻŦāĻĒā§āĻ°ā§āĻŖ āĻ ā§ąāĻĻāĻžāĻ¨ āĻāĻāĻŦāĻĸāĻŧāĻžāĻāĻāĻŋāĻ˛āĨ¤
9. The tiny regions responsible for ferromagnetism are called —. Ferromagnetism-ā§° āĻŦāĻžāĻŦā§ āĻĻāĻžāĻ¯āĻŧā§ āĻ¸ā§°ā§ āĻ āĻā§āĻāĻ˛āĻ¸āĻŽā§āĻšāĻ — āĻŦā§āĻ˛āĻŋ āĻā§ā§ąāĻž āĻšāĻ¯āĻŧāĨ¤
(a) atoms | (b) ions | (c) magnetic domains | (d) nuclei
Ans: (c) magnetic domains
Explanation: Magnetic domains are tiny regions with aligned magnetic moments. āĻŦā§āĻ¯āĻžāĻā§āĻ¯āĻž: Magnetic domains āĻšā§āĻā§ āĻ¸ā§°ā§ āĻ āĻā§āĻāĻ˛ āĻ¯’āĻ¤ āĻā§āĻŽā§āĻŦāĻā§āĻ¯āĻŧ āĻĻāĻŋāĻļ āĻāĻā§ āĻĨāĻžāĻā§āĨ¤
10. Which of the following shows strongest magnetism ? āĻ¤āĻ˛ā§° āĻā§āĻ¨āĻā§ā§ąā§ āĻāĻāĻžāĻāĻ¤āĻā§ āĻļāĻā§āĻ¤āĻŋāĻļāĻžāĻ˛ā§ āĻā§āĻŽā§āĻŦāĻāĻ¤ā§āĻŦ āĻĻā§āĻā§ā§ąāĻžāĻ¯āĻŧ ?
(a) Ferromagnetic substances | (b) Diamagnetic substances | (c) Non-metals | (d) Liquids
Ans: (a) Ferromagnetic substances
Explanation: Ferromagnetic materials show very strong magnetism. āĻŦā§āĻ¯āĻžāĻā§āĻ¯āĻž: Ferromagnetic āĻĒāĻĻāĻžā§°ā§āĻĨāĻ āĻ āĻ¤āĻŋ āĻļāĻā§āĻ¤āĻŋāĻļāĻžāĻ˛ā§ āĻā§āĻŽā§āĻŦāĻāĻ¤ā§āĻŦ āĻĻā§āĻā§ā§ąāĻžāĻ¯āĻŧāĨ¤