Question

Threshold frequency for photoelectric effect on sodium corresponds to a wave length 5000. Its work function is ______.

Options

• 15 Joule

• 10 × 10^–9 Joule

• 4 × 10^–19 Joule

• 4 × 10⁺¹⁹ Joule

Answer 1

4 × 10^–19 Joule

Explanation:

wo = `(nc)/(lambda0)`

= `(6.63 xx 10^-34 xx 3 xx 10^8)/(5000 xx 10^10)`

= 4 × 10^–19 J