# Does light have momentum? Does light have mass? p=mv

Discussion in 'MCAT Study Question Q&A' started by Gauss44, Sep 6, 2014.

1. ### Gauss44 5+ Year Member

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Does light have momentum? Does light have mass? p=mv

2. ### BreakneckWalrus 5+ Year Member

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1. Yes.
2. No.

Photons are massless. However, light still does have momentum. p = mv applies to objects not moving at speeds approaching c. You might recall Einstein's E = mc^2. As I understand it, this is a shortened form of the full equation:

E^2 = (pc)^2 + (mc^2)^2

In which the ability for light to have momentum is seen even though it has no mass.

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3. ### justadream 7+ Year Member

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p = h / wavelength

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