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3 years ago

Question 10 of 10

Physics

1 answer:

Margaret [11]3 years ago

7 0

Answer: D. $5.0(10)^{-38} J$

Explanation:

The energy $E$ of an electromagmetic wave is given by:

$E=\frac{hc}{\lambda}$

Where:

$h=6.626(10)^{-34}J.s$ is the Planck constant

$c=3(10)^{8} m/s$ is the speed of light in vacuum

Then $hc=1.99 (10)^{-25}Jm$

$\lambda=4.0(10)^{12} m$ is the wavelength

Solving:

$E=\frac{1.99 (10)^{-25}Jm}{4.0(10)^{12} m}$

$E=5.0(10)^{-38} J$

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