A plane electromagnetic wave of intensity 6.00 W/m2 strikes a small pocket mirror, of area 30.0 cm2, held perpendicular to the approaching wave.(adsbygoogle = window.adsbygoogle || []).push({});

(a) What momentum does the wave transfer to the mirror each second?

kg · m/s

Ok, well for a perfect reflector, the formula is given as total momentum = 2U (total energy) / c (speed of light = 3e8)

Well from the given info i can find the radation force, which is Force = Radiation Pressure * Area

Radiaton Pressure = 2*Wave intensity / speeed of light (2* since it is a perfect reflector)

But, i have NO absolutely no freaking idea how to solve for U??

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# Homework Help: Momentum and radiation pressure

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