Class 12 Physics Chapter 8 objective type / mcq question answer of Electromagnetic Waves NCERT Solution in Hindi. NCERT Class 12 Physics MCQ Question Answer and Important Question Answer, Textual Question answer also Available for Various Board Students like HBSE, CBSE, UP board, Mp Board, RBSE and some other State Boards.
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NCERT Solution for Class 12 Physics Chapter 8 Electromagnetic Waves MCQ Question Answer.
Electromagnetic Waves Class 12 MCQ Question Answer
1. Which of the following has lowest wave-length ?
(A) Gamma rays
(B) X-rays
(C) Infrared rays
(D) Short radio waves
Answer
Ans. (A) Gamma rays
2. Which electromagnetic wave are used in cellular phones to transmit voice communication in the Ultra High Frequency (UHF) band ?
(A) Microwave
(B) Gamma
(C) Radio
(D) Infra-red
Answer
Ans. (C) Radio
3. Which electromagnetic wave is used to kill germs in water purifiers ?
(A) Microwave
(B) Ultra-violet
(C) Light
(D) X rays
Answer
Ans. (B) Ultra-violet
4. Which electromagnetic wave is used in remote switches of TV sets ?
(A) Microwave
(B) Gamma
(C) Radio
(D) Infra-red
Answer
Ans. (D) Infra-red
5. Which of the following has highest frequency ?
(A) Ultraviolet rays
(B) Long radio waves
(C) Gamma rays
(D) X-rays
Answer
Ans. (C) Gamma rays
6. Which of the following has highest wave-length ?
(A) Gamma rays
(B) X-rays
(C) Ultraviolet rays
(D) Radio waves
Answer
Ans. (D) Radio waves
7. Which of the following has lowest frequency ?
(A) Ultraviolet rays
(B) Long radio waves
(C) Gamma rays
(D) X-rays
Answer
Ans. (B) Long radio waves
8. Electro Magnetic waves were first produced by the ……….
(A) Maxwell
(B) Marconi
(C) Hertz
(D) Bohr
Answer
Ans. (C) Hertz (in 1887)
9. Which of the following is not an electro magnetic wave?
(A) Light wave
(B) Radio wave
(C) Sound wave
(D) Infra-red wave
Answer
Ans. (C) Sound wave
10. Displacement current exists only when
(A) electric field is changing.
(B) magnetic field is changing.
(C) electric field is not changing.
(D) magnetic field is not changing.
Answer
Ans. (A) electric field is changing.
11. Electromagnetic waves used as a diagnostic tool in medicine are
(A) X-rays.
(B) ultraviolet rays.
(C) infrared radiation.
(D) ultrasonic waves.
Answer
Ans. (A) X-rays.
12. A welder wears special glasses to protect his eyes mostly from the harmful effect of
(A) very intense visible light.
(B) infrared radiation.
(C) ultraviolet rays.
(D) microwaves
Answer
Ans. (C) ultraviolet rays.
13. In a travelling plane electromagnetic wave, which of the following have zero average value ?
(A) Magnetic energy and electric energy
(B) Magnetic field and electric field
(C) Magnetic energy and magnetic field
(D) Electric energy and electric field
Answer
Ans. (B) Magnetic field and electric field