Answer:
4.64E14
Explanation:
First convert 645 nm to m = 6.4500E-7m. The equation for finding v with these values is the speed of light/wavelength. so 2.998E8/6.4500E-7m.
so your v or frequency would equal 4.64E14
Fun fact you know this is visible light because the visible light range is within the E14 range.
Climax community is the answer i believe
Use the formula E=mc^2
energy given=<span>8.1 x 10^16 joules
</span>speed of <span>light = 3.00 × 10^8 m/s
</span>
plug in the values we'll get mass=<span>9.0 x 10-1 kg</span>
