Question

If an electromagnetic wave’s frequency doubles in a vacuum, what are the other effects on the wave?

Answer 1

Its wavelength and period are halved and the speed is unchanged or  the wavelength divides in half and speed stays the same.

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Answer 2

Answer:

Wavelength becomes half

Explanation:

If the frequency of the electromagnetic wave is doubled. The wavelength becomes half. The speed of the wave remains constant in a medium.

The relationship between the wavelength, frequency and speed is:

$\lambda =\frac{v}{f}$

So, if frequency doubles, wavelength becomes half.

Also, period $T =\frac{1}{f}$

So, the period would also become half.