A photosensitive metallic surface has work function, h \upsilon 0 . If photons of energy 2h\upsilon _0 fall on this surface, the electrons come out with a maximum velocity of 4 \times 10 6 m/s. When the photon energy is increased to 5 h \upsilon 0 , then maximum velocity of photoelectrons will be

Dual Nature of Radiation and Matter question

2005 · Q140

Dual Nature of Radiation and Matter question

2005 · Q140

View written solutionFree

Correct answer: C

2h ${\nu _0}$ = h ${\nu _0}$ + ${1 \over 2}m{\left( {4 \times {{10}^6}} \right)^2}$

5h ${\nu _0}$ = h ${\nu _0}$ + ${1 \over 2}m{v^2}$

$\Rightarrow$ $4 \times {1 \over 2}m{\left( {4 \times {{10}^6}} \right)^2}$ = ${1 \over 2}m{v^2}$

$\Rightarrow$ v = 8 $\times$ 10⁶ m/s

More from Dual Nature of Radiation and Matter

According to Einstein's photoelectric equation, the graph between the kinetic energy of photoelectrons ejected and the frequency of incident radiation is2004 · MCQ
A photoelectric cell is illuminated by a point source of light 1 m away. When the source is shifted to 2 m then2003 · MCQ
J.J. Thomson's cathode-ray tube experiment demonstrated that2003 · MCQ
The value of Planck's constant is2002 · MCQ
If particles are moving with same velocity, then which has maximum de Broglie wavelength?2002 · MCQ
When ultraviolet rays incident on metal plate then photoelectric effect does not occur, it occurs by incidence of2002 · MCQ
Which of the following is not the property of cathode rays ?2002 · MCQ
In Thomson mass spectrograph $E ⊥ B$ then the velocity of electron beam will be2001 · MCQ

Sign in

Dual Nature of Radiation and Matter question

2005 · Q140

Dual Nature of Radiation and Matter question

2005 · Q140

View written solutionFree

Correct answer: C

2h ${\nu _0}$ = h ${\nu _0}$ + ${1 \over 2}m{\left( {4 \times {{10}^6}} \right)^2}$

5h ${\nu _0}$ = h ${\nu _0}$ + ${1 \over 2}m{v^2}$

$\Rightarrow$ $4 \times {1 \over 2}m{\left( {4 \times {{10}^6}} \right)^2}$ = ${1 \over 2}m{v^2}$

$\Rightarrow$ v = 8 $\times$ 10⁶ m/s