Which of the following statements about electromagnetic waves is/are correct? (1) X-rays in vacuum travel faster than light waves in vacuum.(2) The energy of X-ray photon is greater than that of a light photon(3) Light can be polarised but X-ray cannot.
Correct answer: D. 2 only
- A. 1 and 2
- B. 2 and 3
- C. 1, 2 and 3
- D. 2 only
Explanation
Since X-ray is an electromagnetic wave, they travel with same speed of light in the vacuum that is 3x106 m/s
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Alternating current varies periodically, so phase relationships become essential when current passes through a resistor, capacitor or inductor. The chapter distinguishes resistance from capacitive and inductive reactance, explains phase lead and lag, and connects changing electric and magnetic fields with the production and properties of electromagnetic waves.
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