JEE Advanced | 2014Work, Power and EnergyHard
Question
A metal surface is illuminated by light of two different wavelengths 248 nm and 310 nm. The maximum speeds of the photoelectrons corresponding to these wavelengths are u1 and u2, respectively. If the ratio u1 : u2 = 2 : 1 and hc = 1240 eV nm, the work function of the metal is nearly
Options
A.3.7 eV
B.3.2 eV
C.2.8 eV
D.2.5 eV
Solution
mu12 = 
- Wmu22 = 
- W
- W ( ∵ 
= 2)
= 3W⇒
= 3W ⇒ 16 - 5 = 3 W⇒ 11 = 3 W
⇒ W = 3.7 eV
Create a free account to view solution
View Solution FreeMore Work, Power and Energy Questions
If and displacement , then the work done is :-...A body of mass m1 moving with a velocity 10 ms-1 collides with another body at rest of mass m2. After collision the velo...40. An inductor 20 mH, a capacitor 50 μF and a resistor 40 Ω are connected in series across a source of emf V ...The work functions of metals A and B are in the ratio 1 : 2. If light of frequencies ƒ and 2ƒ are incident on ...A spherical ball of mass 20 kg is stationary at the top of a hill of height 100 m. It rolls down a smooth surface to the...