If the function is continuous at x= then k equals

The function has

In the, following compounds, the order of basicity is :
I)
II)
III)
IV)

Arrange the following carbocations in decreasing order of stability:
I)
II)
III)
IV) 

If and where exists, then is continuous on

The value of f (0) so that the function is continuous at  is

For such questions, we should know formula for different limits.

Light of two different frequencies whose photons have energies and respectively, successively illuminates a metal of work function . The ratio of maximum kinetic energy of the emitted electron will be

4 eV is the energy of the incident photon and the work function in What is the stopping potential

The work functions for sodium and copper are and . Which of them is suitable for a photocell with 4000 light

When yellow light is incident on a surface, no electrons are emitted while green light can emit. If red light is incident on the surface, then

As the intensity of incident light increases

The work function of a photoelectric material is 3.3 eV. The threshold frequency will be equal to

When light falls on a metal surface, the maximum kinetic energy of the emitted photo-electrons depends upon

f(x)= , the value of ‘a’ so that f is continuous function is

The energy of a photon of light with wavelength 5000 is approximately 2.5 eV. This way the energy of an X-ray photon with wavelength 1would be

The energy of a photon of wavelength is given by