the light from a helium neon laser has a wavelength of 632 nanometers in air. the same light has a wavelength of 479.2 in glass. the frequency of the light is the same in air and glass. find the speed of the laser light in glass.

speed (m/s) = wavelength (m) * frequency (1/s)

v = λf

so, for a given frequency, the velocity is directly proportional to the wavelength.

Get v in air, and then you can figure v in glass.

speed = wavelength * frequency

so, the speeds are in the same ratio as the wavelengths

sglass = sair (wglass / wair)

To find the speed of the laser light in glass, we can use the equation:

speed = wavelength × frequency

Since the frequency of the light is the same in air and glass, we can focus on the wavelengths.

In air, the given wavelength is 632 nanometers, which we can convert to meters by dividing by 10^9:

wavelength in air (λ_air) = 632 nm = 632 × 10^-9 m

In glass, the given wavelength is 479.2 nm, again converted to meters:

wavelength in glass (λ_glass) = 479.2 nm = 479.2 × 10^-9 m

Now, we can use the equation to find the speed of light in glass:

speed in glass = wavelength in glass × frequency

Since frequency is the same in both air and glass, we can drop it from the equation, and just compare the ratios of the wavelengths:

speed in glass = (wavelength in glass) / (wavelength in air) × (speed in air)

To obtain the speed in glass, we need to know the speed of light in air. The speed of light in a vacuum or air is approximately 299,792,458 meters per second (m/s).

Therefore, the final equation becomes:

speed in glass = (wavelength in glass / wavelength in air) × (speed in air)
= (479.2 × 10^-9 m) / (632 × 10^-9 m) × (299,792,458 m/s)

Now we can calculate the speed of the laser light in glass:

speed in glass = (479.2 × 10^-9 m) / (632 × 10^-9 m) × (299,792,458 m/s)
≈ 2.28 × 10^8 m/s

So, the speed of the laser light in glass is approximately 2.28 × 10^8 meters per second (m/s).