Question

Work function of li and cu are respectively 2.3ev and 4.0 ev

Answer 1

E = hc/λ
= 1.83 eV, which is less than ϕ0.
Photoelectric emission cannot take place.
Q10. The de-Broglie wavelength of a particle of kinetic energy K is λ. What would be the wavelength
of the particle, if its kinetic energy were K/4?
Ans10. λ= h/√2mK
When kinetic energy is K/4
λ1 = h/√
2mK
4
= 2λ.

Answer 2

$\mathcal{\red{\huge{Heya\:mate\:!!}}}$

$\mathtt{Here\:is\:ur\:@nswer}$ :

⎇ λ= h/√2mK

When kinetic energy is K/4

λ1 = h/√

2mK

4

= 2λ.