Physics

Problem

Two materials exhibit the following linear relations for the maximum kinetic energy

K_{\text{max}}

(in joules) of emitted photoelectrons as a function of light frequency

f

(in hertz): Material A:

K_{\text{max}} = 6.60\times10^{-34} f - 2.40\times10^{-19}

Material B:

K_{\text{max}} = 6.60\times10^{-34} f - 4.00\times10^{-19}

Calculate the threshold frequency for each material.