The video explains why thunder is heard after lightning, despite both occurring almost simultaneously. This is due to the different speeds at which light and sound waves travel. Light waves move faster than sound waves, causing the flash to be seen before the sound is heard. The video also covers how wave speed varies with wave type and medium, and how to calculate wave speed using frequency and wavelength.

Why do we see lightning before we hear thunder?

• Because thunder is quieter than lightning

• Because they occur at different times

• Because sound travels faster than light

• Because light travels faster than sound

What type of waves are involved in the phenomenon of lightning and thunder?

• Both electromagnetic and mechanical waves

• Neither electromagnetic nor mechanical waves

• Only electromagnetic waves

• Only mechanical waves

What factors affect the speed of a wave?

• The color of the wave

• The type of wave and the medium it travels through

• The time of day

• The temperature of the air

How can you calculate the speed of a wave?

• By dividing its frequency by its wavelength

• By multiplying its frequency by its wavelength

• By subtracting its frequency from its wavelength

• By adding its frequency and wavelength

What is the relationship between wave speed, frequency, and wavelength?

• Wave speed is the sum of frequency and wavelength

• Wave speed is the product of frequency and wavelength

• Wave speed is the ratio of frequency to wavelength

• Wave speed is the difference between frequency and wavelength