Download App

Physics M.C.Q (1 Marks)

Electromagnetic Waves · CBSE STD 12 Science (CBSE - English Medium). 26 questions.

Questions

M.C.Q (1 Marks)

🎯

Test yourself on this topic

26 questions · timed · auto-graded

MCQ 11 Mark
The formula for displacement $\left( I _d\right)$ is :
  • A
    $\mu_0 \frac{d \phi_{ E }}{d t}$
  • B
    $\mu_0 \in_0 \frac{d \phi_{ E }}{d t}$
  • ✓
    $\epsilon_0 \frac{d \phi_{ E }}{d t}$
  • D
    $\frac{1}{\epsilon_0} \frac{d \phi_{ E }}{d t}$
Answer
Correct option: C.
$\epsilon_0 \frac{d \phi_{ E }}{d t}$
(c)$\epsilon_0 \frac{d \phi_{ E }}{d t}$
View full question & answer→
MCQ 21 Mark
In any electromagnetic wave, electric and magnetic field are represented by $\vec{E}$ and $\vec{B}$ respectively. The direction of propagation of this wave is along :
  • A
    $\overrightarrow{ B }$
  • B
    $\overrightarrow{ E }$
  • ✓
    $\vec{E} \times \vec{B}$
  • D
    $\vec{B} \times \vec{E}$
Answer
Correct option: C.
$\vec{E} \times \vec{B}$
(c)$\vec{E} \times \vec{B}$
View full question & answer→
MCQ 31 Mark
Range of wavelength of X-rays is:
  • A
    $10^{-4} m$ to $10^{-8} m$
  • ✓
    $10^{-8} m$ to $10^{-13} m$
  • C
    $10^8 m$ to $10^{13} m$
  • D
    None of these
Answer
Correct option: B.
$10^{-8} m$ to $10^{-13} m$
(b)$10^{-8} m$ to $10^{-13} m$
View full question & answer→
MCQ 41 Mark
Displacement current is same as:
  • A
    r.m.s. current
  • ✓
    Conduction current
  • C
    Peak current
  • D
    None of these
Answer
Correct option: B.
Conduction current
(b)Conduction current
View full question & answer→
MCQ 51 Mark
Which of the following wave is used in long distance communication?
  • A
    Visible Light
  • ✓
    Micro waves
  • C
    Ultraviolet
  • D
    Infrared
Answer
Correct option: B.
Micro waves
(b)Micro waves
View full question & answer→
MCQ 61 Mark
Electromagnetic waves
  • ✓
    Follow the principle of superposition
  • B
    Do not follow the principle of superposition
  • C
    Only show superposition
  • D
    Only show interference
Answer
Correct option: A.
Follow the principle of superposition
(a)Follow the principle of superposition
View full question & answer→
MCQ 71 Mark
Characteristic of electromagnetic wave is shown by:
  • A
    Light and sound
  • ✓
    Light and X-rays
  • C
    X-rays and electrons
  • D
    Light and photon
Answer
Correct option: B.
Light and X-rays
(b)Light and X-rays
View full question & answer→
MCQ 81 Mark
Value of refractive index for any medium is:
  • A
    $\frac{1}{\sqrt{\mu_r \in_r}}$
  • B
    $\sqrt{\mu_r / \epsilon_r}$
  • C
    $\sqrt{\epsilon_r / \mu_r}$
  • ✓
    $\sqrt{\mu_r \epsilon_r}$
Answer
Correct option: D.
$\sqrt{\mu_r \epsilon_r}$
(d)$\sqrt{\mu_r \epsilon_r}$
View full question & answer→
MCQ 91 Mark
If $\mu_0$ and $\epsilon_0$ be permeability and electrical permittivity of vacuum respectively, then velocity of electromagnetic waves in vacuum is :
  • A
    $\sqrt{\mu_0 \epsilon_0}$
  • ✓
    $\frac{1}{\sqrt{\mu_0 \epsilon_0}}$
  • C
    $\frac{\mu_0}{\epsilon_0}$
  • D
    $\sqrt{\mu_0 / \epsilon_0}$
Answer
Correct option: B.
$\frac{1}{\sqrt{\mu_0 \epsilon_0}}$
(b)$\frac{1}{\sqrt{\mu_0 \epsilon_0}}$
View full question & answer→
MCQ 101 Mark
Light waves are:
  • A
    Longitudinal mechanical waves
  • B
    Transverse elastic waves
  • C
    Longitudinal elastic waves
  • ✓
    Transverse electromagnetic waves
Answer
Correct option: D.
Transverse electromagnetic waves
(d)Transverse electromagnetic waves
View full question & answer→
MCQ 111 Mark
Principle of existence of electromagnetic waves was given by:
  • A
    Newton
  • ✓
    Maxwell
  • C
    Hertz
  • D
    Huygens
Answer
Correct option: B.
Maxwell
(b)Maxwell
View full question & answer→
MCQ 121 Mark
That part of electromagnetic spectrum which is used to study crystal structure is:
  • A
    Micro waves
  • B
    Radio waves
  • ✓
    X-rays
  • D
    Infrared rays
Answer
Correct option: C.
X-rays
(c)X-rays
View full question & answer→
MCQ 131 Mark
Which of the following waves are not electromagnetic?
  • A
    Radio waves
  • ✓
    Sound waves
  • C
    Infrared rays
  • D
    Micro waves
Answer
Correct option: B.
Sound waves
(b)Sound waves
View full question & answer→
MCQ 141 Mark
Out of the following, waves of which frequency can penetrate ionosphere?
  • A
    Greater than 5 Hertz
  • B
    Greater than 10 MHz
  • ✓
    Greater than 20 MHz
  • D
    Greater than 15 MHz
Answer
Correct option: C.
Greater than 20 MHz
(c)Greater than 20 MHz
View full question & answer→
MCQ 151 Mark
Ozone layer protects us from which harmful radiations coming from the sun?
  • A
    X-rays
  • B
    Gamma rays
  • ✓
    Ultra-violet rays
  • D
    Micro waves
Answer
Correct option: C.
Ultra-violet rays
(c)Ultra-violet rays
View full question & answer→
MCQ 161 Mark
Speed of electromagnetic waves in vacuum is:
  • ✓
    $3 \times 10^8 m / s$
  • B
    $3 \times 10^7 m / s$
  • C
    $3 \times 10^6 m / s$
  • D
    $3 \times 10^10 m / s$
Answer
Correct option: A.
$3 \times 10^8 m / s$
(a)$3 \times 10^8 m / s$
View full question & answer→
MCQ 171 Mark
Out of the following, which colour's wavelength is more than the wavelength of yellow colour?
  • A
    Green
  • B
    Blue
  • ✓
    Red
  • D
    Violet
Answer
Correct option: C.
Red
(c)Red
View full question & answer→
MCQ 181 Mark
In electromagnetic spectrum, the component whose wavelength is minimum is:
  • ✓
    Gamma rays
  • B
    X-rays
  • C
    Radio waves
  • D
    Micro waves
Answer
Correct option: A.
Gamma rays
(a)Gamma rays
View full question & answer→
MCQ 191 Mark
Nature of electromagnetic waves is:
  • A
    Longitudinal
  • ✓
    Transverse
  • C
    Mechanical
  • D
    Longitudinal and transverse
Answer
Correct option: B.
Transverse
(b)Transverse
View full question & answer→
MCQ 201 Mark
If $\lambda_v, \lambda_{ x }$ and $\lambda_{ m }$ represents wavelengths of visible lights, X-rays and microwaves respectively, then :
  • A
    $\lambda_{ m }>\lambda_{ x }>\lambda_{ y }$
  • ✓
    $\lambda_{ m }>\lambda_{ v }>\lambda_{ x }$
  • C
    $\lambda_{ v }>\lambda_{ x }>\lambda_{ m }$
  • D
    $\lambda_{ v }>\lambda_{ m }>\lambda_{ x }$
Answer
Correct option: B.
$\lambda_{ m }>\lambda_{ v }>\lambda_{ x }$
(b)$\lambda_{ m }>\lambda_{ v }>\lambda_{ x }$
View full question & answer→
MCQ 211 Mark
Crystal structure is studied by:
  • A
    Ultraviolet rays
  • ✓
    X-rays
  • C
    Infrared radiations
  • D
    Micro waves
Answer
Correct option: B.
X-rays
(b)X-rays
View full question & answer→
MCQ 221 Mark
Out of the following, the one whose frequency is minimum is:
  • ✓
    Infrared rays
  • B
    X-rays
  • C
    Ultra-violet rays
  • D
    Gamma rays
Answer
Correct option: A.
Infrared rays
(a)Infrared rays
View full question & answer→
MCQ 231 Mark
Out of the following waves of the Sun, the wave which is used as an electrical energy is:
  • A
    Radio waves
  • ✓
    Infrared rays
  • C
    Visible light
  • D
    Micro waves
Answer
Correct option: B.
Infrared rays
(b)Infrared rays
View full question & answer→
MCQ 241 Mark
Wavelength of visible light is
  • A
    7800 A to 1500 A
  • B
    1 A to 100 A
  • ✓
    4000 A to 8000 A
  • D
    5000 A to 1200 A
Answer
Correct option: C.
4000 A to 8000 A
(c)4000 A to 8000 A
View full question & answer→
MCQ 251 Mark
Which of the following is an electromagnetic wave?
  • A
    Positive rays
  • B
    Alpha rays
  • C
    Beta rays
  • ✓
    Gamma rays
Answer
Correct option: D.
Gamma rays
(d)Gamma rays
View full question & answer→
MCQ 261 Mark
Main source of electromagnetic waves is:
  • A
    Stationary charge
  • B
    Charge moving with uniform speed
  • ✓
    Accelerated charge
  • D
    None of the above
Answer
Correct option: C.
Accelerated charge
(c)Accelerated charge
View full question & answer→
Generate Paper FreeAll Electromagnetic Waves topics