1
JEE Main 2022 (Online) 29th June Evening Shift
+4
-1

The electric field at a point associated with a light wave is given by

E = 200 [sin (6 $$\times$$ 1015)t + sin (9 $$\times$$ 1015)t] Vm$$-$$1

Given : h = 4.14 $$\times$$ 10$$-$$15 eVs

If this light falls on a metal surface having a work function of 2.50 eV, the maximum kinetic energy of the photoelectrons will be

A
1.90 eV
B
3.27 eV
C
3.60 eV
D
3.42 eV
2
JEE Main 2022 (Online) 29th June Morning Shift
+4
-1

Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R :

Assertion A : The photoelectric effect does not takes place, if the energy of the incident radiation is less than the work function of a metal.

Reason R : Kinetic energy of the photoelectrons is zero, if the energy of the incident radiation is equal to the work function of a metal.

In the light of the above statements, choose the most appropriate answer from the options given below.

A
Both A and R are correct and R is the correct explanation of A.
B
Both A and R are correct but R is not the correct explanation of A.
C
A is correct but R is not correct.
D
A is not correct but R is correct.
3
JEE Main 2022 (Online) 28th June Evening Shift
+4
-1

Let K1 and K2 be the maximum kinetic energies of photo-electrons emitted when two monochromatic beams of wavelength $$\lambda$$1 and $$\lambda$$2, respectively are incident on a metallic surface. If $$\lambda$$1 = 3$$\lambda$$2 then :

A
$${K_1} > {{{K_2}} \over 3}$$
B
$${K_1} < {{{K_2}} \over 3}$$
C
$${K_1} = {{{K_2}} \over 3}$$
D
$${K_2} = {{{K_1}} \over 3}$$
4
JEE Main 2022 (Online) 28th June Morning Shift
+4
-1

The de Broglie wavelengths for an electron and a photon are $$\lambda$$e and $$\lambda$$p respectively. For the same kinetic energy of electron and photon, which of the following presents the correct relation between the de Broglie wavelengths of two ?

A
$${\lambda _p} \propto \lambda _e^2$$
B
$${\lambda _p} \propto {\lambda _e}$$
C
$${\lambda _p} \propto \sqrt {{\lambda _e}}$$
D
$${\lambda _p} \propto \sqrt {{1 \over {{\lambda _e}}}}$$
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