The Work Function of a Particular Metal Is $4.20 \times 10 ^ { - 19 } \mathrm {~J}$

Multiple Choice

The work function of a particular metal is $4.20 \times 10 ^ { - 19 } \mathrm {~J}$ . What is the photoelectric cutoff (threshold) wavelength for this metal? $\left( c = 3.00 \times 10 ^ { 8 } \mathrm {~m} / \mathrm { s } , h = 6.626 \times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s } \right)$

A) $308 \mathrm {~nm}$
B) $554 \mathrm {~nm}$
C) $393 \mathrm {~nm}$
D) $473 \mathrm {~nm}$