Consider the situation of the previous problem. Consider the fastest electron emitted parallel to the large metal plate. Find the displacement of this electron parallel to its initial velocity before it strikes the large metal plate.

Explanation

Here electric field of metal plate ,
E = P / E_o = 1 xx 10^(19) / 8.85 xx 10^(-12) `
` = 113 V / m`
Accelaration, a = `qE / m `
`= 1.6 xx 10^(-19) xx 113 / 9.1 xx 10^(-31) = 19.87 xx 10^(12) `
` t = (sqrt 2y/ a ) = (sqrt 2 xx 20 xxx 10^(-2) / 19.87 xx 10^(12)) `
` = 1.41 xx10^(-7) sec`
K.E. = hc / lambda - W = 1.2eV` ltbrge 1.41 xx 10^(-7)sec `
` =1.2 xx 1.6 xx 10^(-19) J `
`[:. in problem 31 : KE = 1.2 eV ]`
`:. V = (sqrt 2KE / m) `
` = ( sqrt 2 xx 1.2 xx 1.6 xx 10^(-19)/ 4.1 xx 10^(-31)`
`= 0.665 xx 10^(-6) m / sec`.
`:. Horizontal displacemnt
` = Vxx t `
` = 0.665 xx 10^(-6) xx 1.4 xx 10^(-7) `
` 0.092 m = 9.2 cm`