Radiation of wavelength 180 nm eject photoelectrons from a plate whose work function is 2.0 eV. If a uniform magnetic field of flux density5.0xx10^(-5)T is applied parallel to plate, what should be the radius of the path followed by electrons ejected normally from the plate with maximum energy:

Radiation of wavelength 180 nm eject photoelectrons from a plate whose

1.	Radiation of wavelength 180 nm eject photoelectrons from a plate whose work function is 2.0 eV. If a uniform magnetic field of flux density5.0xx10^(-5)T is applied parallel to plate, what should be the radius of the path followed by electrons ejected normally from the plate with maximum energy:
Answer» 0.074 m 0.592m 0.419m 0.149 Solution :`E-hv-w=(hc)/(lambda)-w` Here `lambda= nm=180xx10^(-19)m` `w=20eV=20xx16xx10^(-9)J` `:.E=78xx10^(-19)J` Also `(1)/(2) mv^(2)=E:. V= sqrt((2E)/(m))` So `v=sqrt((2xx78xx10^(-19))/(91xx10^(-31)))=131xx10^(6)m//s` Radius r in a magnetic field of induction B is given by `BEV=(mv^(2))/(r) or r=(mv)/(eB)` Using `B=5xx10^(-5)T` Then `r=0149m`

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Radiation of wavelength 180 nm eject photoelectrons from a plate whose work function is 2.0 eV. If a uniform magnetic field of flux density5.0xx10^(-5)T is applied parallel to plate, what should be the radius of the path followed by electrons ejected normally from the plate with maximum energy:

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