photoelectric affect experiments are performer using ther different medal plates $p,q$ and$r$ having work functionphi_(p) = 2.0 eV, phi_(e) = 2.5 eV$\text{and}$phi_(r) = 3.0 eV$respectivelyAlightbeamconta\in \in gwave\le n>hof$550nm , 450 nm$\text{and}$350nm $withequal\int ensitiesillu\min ateseachoftheplate.Thec\text{or}rect$1 -V$graphf\text{or}the\exp erimentis$ [Take hc = 1240 eV nm]

Answer: ASolution: The energy possessed by photons of wavelength
$550nmis\frac{1240}{550}=2.25eV$
The energy by photons of wavelength
$450is\frac{1240}{450}=2.76eV$
The energy possessed by photons of wavelength
$3450nmis\frac{1240}{350}=3.54eV$
For metal plate p :
${\varphi }_p=2eV$
All the wavelength are capable of ejecting electrons . Therfore the currect is maximum . Also as the work function is loewst in p, kinetic energy of ejected potential is bighast.
for mjatal plate q :
${\varphi }_q=25eV$
photoes of wavelength $550$ nm will not be able to iject electrons and therefore , the currect is smaller than p . The work function is greater then q therfore the stopping potential in compararison to p.
for metal plate r :
${\varphi }_r=3eV$ Only wavelength of $350$ nm will be able to eject and therefore , currect is minimum. Also the stopping potential is least.