A scientist is doing research to try and find the ideal energy that a photon needs to cause an electron to flow out of a sheet of iron. She finds that the photons being emitted from her source did not have enough energy to cause an electron to flow out of the iron sheet.
Using the paragraph, what can you conclude about the scientist's source of photons?
(1 point)
She was using electromagnetic waves with energy that was too high.
She was using light with frequencies that were too high.
She was using infrared waves when she should have been using gamma radiation.
She was using radiation with wavelengths that were too long.