Choose the correct option:
1. | The radiation in increasing order of frequency are radio waves, microwaves, infrared, visible, ultraviolet, X-rays, gamma rays. |
2. | The wavelength of colours in increasing order is violet, indigo, green, yellow, orange and red. |
3. | The speed of light is maximum in vacuum. |
4. | All options are correct. |
Which colour of light has the longest wavelength?
1. violet
2. red
3. blue
4. green
Which statement is correct for X-rays and gamma rays?
1. | X-rays are emitted from electronic transitions while gamma rays are emitted from nuclear transitions. |
2. | X-rays have less penetrating power in comparison to gamma rays, in general. |
3. | The frequency of gamma rays is more than the frequency of X-rays, in general. |
4. | All of the above. |
If \(\lambda_{v}, \lambda_{x},\) and \(\lambda_{m}\) represent the wavelengths of visible light, \(x\text-\)rays and microwaves respectively, then:
1. \( \lambda_{m}>\lambda_{x}>\lambda_{v} \)
2. \( \lambda_{v}>\lambda_{m}>\lambda_{x } \)
3. \( \lambda_{v}>\lambda_{x}>\lambda_{m }\)
4. \(\lambda_{m}>\lambda_{v}>\lambda_{x}\)
Which of the following is not an electromagnetic wave?
1. Radio wave
2. Micro wave
3. Cosmic rays
4. -rays
The most penetrating radiation out of the following is:
1. \(X\text-\)rays
2. \(\beta\text-\)rays
3. \(\alpha\text-\)rays
4. \(\gamma\text-\)rays
The condition under which a microwave oven heats up a food item containing water molecules most efficiently is:
1. | the frequency of the microwave must match the resonant frequency of the water molecules. |
2. | the frequency of the microwave has no relation to the natural frequency of water molecules. |
3. | microwave are heatwaves, so always produce heating. |
4. | infrared waves produce heating in a microwave oven. |
The decreasing order of the wavelength of infrared, microwave, ultraviolet and gamma rays is:
1. | Gamma rays, ultraviolet, infrared, microwaves |
2. | Microwaves, gamma rays, infrared, ultraviolet |
3. | Infrared, microwave, ultraviolet, gamma rays |
4. | Microwave, infrared, ultraviolet, gamma rays |
1. | \( b>a>c \) | 2. | \( a>b>c \) |
3. | \( c>b>a \) | 4. | \( a>c>b\) |
List I | List II | ||
(a) | Ultraviolet rays | (i) | Study crystal structure |
(b) | Microwaves | (ii) | Greenhouse effect |
(c) | Infrared waves | (iii) | Sterilizing surgical instrument |
(d) | X-rays | (iv) | Radar system |
1. | (a) – (iii), (b) – (iv), (c) – (ii), (d) – (i) |
2. | (a) – (iii), (b) – (i), (c) – (ii), (d) – (iv) |
3. | (a) – (iv), (b) – (iii), (c) – (ii), (d) – (i) |
4. | (a) – (iii), (b) – (iv), (c) – (i), (d) – (ii) |