Light of frequencies and produces stopping potentials of and

PHYSICS · Subjective · A Level · Physics · Particles and radiation · Particles and radiation

Problem

Light of frequencies

5.0 \times 10^{14}\,\text{Hz}

and

8.0 \times 10^{14}\,\text{Hz}

produces stopping potentials of

0.5\,\text{V}

and

2.0\,\text{V}

, respectively, for a certain metal. Calculate the value of Planck’s constant (give your answer in J·s to two significant figures).