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प्रश्न
Answer briefly.
Does an ordinary electric lamp emit EM waves?
उत्तर
Yes, an ordinary electric lamp emits EM waves.
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संबंधित प्रश्न
What role dose infra-red radiation play in physical therapy?
What is the range of the wavelength of the following electromagnetic waves?
(a) Infrared.
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(a) Micro waves .
State the approximate range of wavelength associated with the ultraviolet rays.
State the approximate range of wavelength associated with visible light.
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(Use Planck constant h = 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
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Name the scientist who discovered Infra-red waves
Two waves A and B have wavelength 0.01 Å and 9000 Å respectively.
Name the two waves. compare the speeds of these waves when they travel in vacuum.
| 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.
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(e) Name one detector for each of the radiation.
(f) Name one use of each of the radiation.
Answer the following question.
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Choose the correct option.
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Answer briefly.
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Answer briefly.
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