The speed of electromagnetic waves in the air is about

PHYSICS · Single correct · CBSE · Physics · Electromagnetic Waves · Electromagnetic Waves

Problem

3 \times 10^8 \text{ ms}^{-1}

. Which of the following is the best estimate of the frequency of a microwave of wavelength 3 cm? (1) 10 Hz (2) 10 kHz (3) 10 MHz (4) 10 GHz