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प्रश्न
Which of the following is true for a cathode ray?
(a) It travels in a straight line.
(b) It emits an X-ray when it strikes a metal.
(c) It is an electromagnetic wave.
(d) It is not deflected by a magnetic field.
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उत्तर
(a) It travels in a straight line.
(b) It emits an X-ray when it strikes a metal.
A cathode ray travels in a straight line. When cathode rays strike a solid metal, X-rays are emitted from the metal. When a cathode ray tube is brought in a magnetic field, the path of cathode rays gets deflected. Cathode rays are the matter waves that consists of electrons thus they are not electromagnetic waves.
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