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प्रश्न
Give any two uses of infrared waves.
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उत्तर १
For therapeutic purposes and long distance photography.
उत्तर २
- TV Remote Controls: IR LEDs are used to transmit encoded signals to electronic devices.
- Physical Therapy: IR lamps are used to treat muscular strains and provide warmth to tissues.
- Night Vision: IR sensors are used in goggles and cameras to detect heat signatures in the dark.
Notes
Students can refer to the provided solutions based on their preferred marks.
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संबंधित प्रश्न
Name the parts of the electromagnetic spectrum which is
used to treat muscular strain.
Write in brief, how these waves can be produced.
Optical and radio telescopes are built on the ground but X-ray astronomy is possible only from satellites orbiting the earth. Why?
Name two sources, each of infrared radiations and ultraviolet radiations.
X-ray and visible light travel at the same speed in vacuum. Do they travel at the same speed in glass?
The Kβ X-rays from certain elements are given below. Draw a Moseley-type plot of √v versus Z for Kβ radiation.
| Element | Ne | P | Ca | Mn | Zn | Br |
| Energy (keV) | 0.858 | 2.14 | 4.02 | 6.51 | 9.57 | 13.3 |
The wavelengths of Kα and Lα X-rays of a material are 21.3 pm and 141 pm respectively. Find the wavelength of Kβ X-ray of the material.
(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
When 40 kV is applied across an X-ray tube, X-ray is obtained with a maximum frequency of 9.7 × 1018 Hz. Calculate the value of Planck constant from these data.
(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
| Gamma rays | D | C | Visible light | B | A |
The above table shows different parts of the electromagnetic spectrum.
(a) Identify the parts of the spectrum marked as A, B, C and D.
(b) Which of the radiations A or B has the higher frequency?
(c) State two properties which are common to all parts of the electromagnetic spectrum.
(d) Name one source of each of the radiation of electromagnetic spectrum.
(e) Name one detector for each of the radiation.
(f) Name one use of each of the radiation.
Choose the correct option.
Earth’s atmosphere is richest in
Answer briefly.
Can we produce a pure electric or magnetic wave in space? Why?
