A source of monochromatic radiation wavelength 400   nm provides 1000   J of energy in 10 seconds. When this radiation falls on the surface of sodium, x × 10 20 electrons are ejected per second. Assume that wavelength 400   nm is sufficient for ejection of electron from the surface of sodium metal. The value of x is ______. (Nearest integer) h = 6 . 626 × 10 - 34   Js

Step-by-step solution

Total energy provided by Source per second = 1000 10 = 100   J Energy required to eject electron = hc λ = 6 . 626 × 10 - 34 400 × 10 - 9 × 3 × 10 8 Number of electrons ejected = 100 6 . 626 × 10 - 34 × 3 × 10 8 400 × 10 - 9 = 400 × 10 - 7 × 10 26 6 . 626 × 3 = 40 × 10 - 20 6 . 626 × 3 = 2 . 01 × 10 20