When light of wavelength 240 nm falls on a cobalt surface, electrons having a maximum kinetic energy of 0.17 ev are emitted. find values for the following. (a) the work function of cobalt ev (b) the cutoff wavelength nm (c) the frequency corresponding to the cutoff wavelength hz

(a) 5.04 eV (B) 248.14 nm (c)

Explanation:

We have given Wavelength of the light  \lambda = 240 nm

According to plank's rule ,energy of light

Maximum KE of emitted electron i= 0.17 eV

Part( A) Using Einstien's equation

, here is work function.

= 5.21 eV-0.17 eV = 5.04 eV

Part( B) We have to find cutoff wavelength

Part (C) In this part we have to find the cutoff frequency

in simple terms, the principle states that the buoyancy force on an object is equal to the weight of the fluid displaced by the object, or the density of the fluid multiplied by the submerged volume times the gravitational acceleration, g. this is also known as upthrust.

neither accurate nor precise.