Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app

JEE Main 2009

Exam: JEE Main
Year: 2009
Subject: Physics
Chapter: Dual Nature of Matter

JEE Main 2009 · Physics · Dual Nature of Matter

The surface of a metal is illuminated with the light of 400 ~nm ....

The surface of a metal is illuminated with the light of

400 \mathrm{~nm}

. The kinetic energy of the ejected photoelectrons was found to be

1.68 \mathrm{eV}

. The work function of the metal is

(\mathrm{hc}=1240 \mathrm{eV} \mathrm{nm})

Options

A $3.09 \mathrm{eV}$
B $1.41 \mathrm{eV}$
C $151 \mathrm{eV}$
D $1.68 \mathrm{eV}$

Correct answer

B. $1.41 \mathrm{eV}$

Step-by-step solution

\begin{aligned} \frac{1}{2} \mathrm{mv}^2=\mathrm{eV}_{\mathrm{o}}=1.68 \mathrm{eV} \Rightarrow \mathrm{hv}=\frac{\mathrm{hc}}{\lambda}=\frac{1240 \mathrm{evnm}}{400 \mathrm{ nm}}=3.1 \mathrm{eV} \Rightarrow3.1 \mathrm{eV}=\mathrm{W}_{0}+1.6 \mathrm{eV}\\ & \therefore \quad \mathrm{W}_{0}=1.42 \mathrm{eV} \end{aligned}

Practice Dual Nature of Matter on Quantrex Academy →

More from Dual Nature of Matter

K_1 and K_2 be the maximum kinetic energies of photoelectrons emitted from a surface of a… JEE Main 2026 The de Broglie wavelength for an electron accelerated through the potential difference of… JEE Main 2026 Given below are two statements: one is labelled as Assertion (A) and the other is… JEE Main 2026 An electron is travelling with a velocity v in free space and when it enters a medium… JEE Main 2026 An electron of mass m is moving in an electric field E = -2E_0 i ( E_0 = constant > 0 )… JEE Main 2026 Light source having wavelength 331 nm is used to generate photo-electrons whose stopping… JEE Main 2026 Match the LIST-I with LIST-II List-I List-II A. Planck's constant I. ML^2T^ -2 B.… JEE Main 2026 The de Broglie wavelength associated with an electron accelerated through a potential… JEE Main 2026 Full Dual Nature of Matter list All JEE Main PYQs