Electromagnetic Spectrum

Q.

What is interference of light?

Q.

Arrange the rays in electromagnetic spectrum according to the increasing order of wavelength.
(1) Infrared rays, (2) X rays, (3) Radiowaves, (4) Microwaves, (5) Gamma rays, (6) UV rays.

1. 5-6-4-3-2-1

2. 5-2-6-1-4-3

3. 3-4-1-6-2-5

4. 1-4-3-5-2-6

Q.

What are the 7 types of electromagnetic waves and their uses.

Q.

Which of following can not be polarized

1. Radio waves

2. Ultraviolet rays

3. Infrared rays

4. Ultrasonic waves

Q.

Microwaves have a wavelength in the range of _____.

Q.

The speed of electromagnetic waves in a vacuum depends upon the source of radiation. It

1. increases as we move from γ-rays to radio waves

2. decreases as we move from γ-rays to radio waves

3. is the same for all of them

4. None of the above

Q.

Why light cannot travel through opaque objects and why they can travel through transparent object ?

Q.

The electromagnetic spectrum is?

Q.

An electromagnetic wave, going through a vacuum is described by $E=E0\sin (kx-\omega t)$. Which of the following is independent of wavelength?

1. k

2. $\omega$

3. $\frac{k}{\omega }$

4. $\omega k$

Q.

Match the list 1 with list 2

Column 1	Column 2
Source of microwave frequency	Radioactive decay of the nucleus
Source of infrared frequency	Magnetron
Source of Gamma Rays	Inner shell electrons
Source of X-rays	The vibration of atoms and molecules

Q.

Infrared radiations are also known as heat waves. Why? Also, name the radiation that are next to infrared radiation with (a) Shorter wavelength (b) Longer wavelength.

Q.

The order in which the rays in the electromagnetic spectrum are arranged is:-

Infrared rays - X rays - Radiowaves - Microwaves - Gamma rays - UV rays - Visible

1. True

2. False

Q.

What is common to all electromagnetic radiations?

Q.

The wavelength of violet color is ________________.

Q.

Arrange the following electromagnetic waves in the descending order of their wavelengths:

(a) microwaves (b) IR rays

(c) UV radiations (d) $\gamma$ rays

Q.

Similar to sound, light cannot travel in a vacuum.

1. True

2. False

Q.

What is colour of danger signals? Why? [2 MARKS]

Q.

Name any two electromagnetic waves which have a frequency higher than that of violet light.

1. Ultraviolet radiations and Microwaves

2. Ultraviolet radiations and X-rays

3. X-rays and Radiowaves

4. Infrared Radiations and Gamma-rays

Q.

What do you understand by the invisible spectrum ?

Q.

An electromagnetic wave has a frequency of 500 MHz and a wavelength of 60 cm.

(a) Calculate the speed of the wave.

(b) Name the medium through which it is travelling.

Q.

20waves passes throw a point in 2sec . If the distance between the crest and the adjacent troughs is 1.5 m calculate the frequency, wavelength and velocity.

Q.

The radiations emitted by a hot furnace are ______.

1. ultra-violet

2. infra-red

3. micro waves

4. X-rays

Q. Speed of light with the increase in its wavelength when it travel in a given medium.

1. increases
2. decreases
3. remain constant

Q. Why must the size of the reflector be larger than the wavelength of the sound wave for reflection to take place?

Q. What happens when a ray fo white light passes through a glass prism?

Q.

Which ray in Electromagnetic Spectrum is present in cosmic radiation?

1. UV rays

2. Gamma rays

3. Visible light

4. Infrared rays

Q. Why there is colours were seen on the TV (television) screen when we put the magnet closer? And why those colours are green and red only?

Q.

Mention three properties of infrared radiations similar to the visible light.

Q.

An electromagnetic wave has a frequency of 500 MHz and a wavelength of 60 cm, then find the speed of the wave.

1. $6\times {10}^{8}m/s$

2. $3\times {10}^{8}m/s$

3. $9\times {10}^{8}m/s$

4. $12\times {10}^{8}m/s$

Q.

(a) Arrange the following radiations in the order of their increasing wavelength :

X rays, infrared rays, radio waves, gamma rays, and microwaves.

(b) Name the radiation which is used for satellite communication.