Light with a frequency of 5.70×10^14 Hz travels in a block of glass that has an index of refraction of 1.56. What is the wavelength of the light in the glass?

✔First you have to calculate the light's speed in the glass,

You know that in the air and in the void (where the refraction index n is zero) the light's speed C corresponds to 3,0 x 10^8 m/s

So We have :

V = C/n

✔ Now, you know the light's speed in glass, and you know that : the wavelength λ is the quotient of light's speed V on its frequency ν, so :

λ = V/ ν

a.metals can become magnetic if they have many spinning electrons that create magnetic fields.d.only some metals are attracted by magnets; these metals are called ferromagnetic.

d.wrapping an insulated wire around a metal with ferromagnetic properties and applying an electric current.

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