Question 1 :
The energy of a $K$-electron in tungsten is $-20keV$ and of an $L$-electrons is $-2keV$. The wavelength of X-rays emitted when there is electron jump from $L$ to $K$ shell:

Question 2 :
According to Heisenberg's uncertainty principle, which of the following statement is true ?<br/>

Question 3 :
An electron accelerated under a p.d. of V volt has&#160;a certain wavelength $\lambda$ . Mass of the proton is&#160;2000 times the mass of an electron. If the proton&#160;has to have the same wavelength $\lambda$ , then it will&#160;have to be accelerated under p.d. of (volts):<br/>

Question 4 :
A microscopic particle of mass $10^{-12}$ kg is movingwith a velocity of $10^{2}$ m/s. Then the de-Brogliewavelength associated with the particle is<br>

Question 6 :
The momentum ( in Kg-m/s)of an electron having wavelength2$A^{0}$ $(h=6.62 \times10^{-34}Js.)$<br>

Question 7 :
The relative uncertainty in the period of a satellite orbiting around the earth is $10^{-2}$. If the relative uncertainty in the radius of the orbit is negligible, the relative uncertainty in the mass of the earth is :

Question 8 :
A particle moves in a closed orbit around the origin, due to a force which is directed towards the origin. The de Broglie wavelength of the particle varies cyclically between two values ${ \lambda }_{ 1 }$ and ${ \lambda }_{ 2 }$ with ${ \lambda }_{ 1 }&gt;{ \lambda }_{ 2 }.$ Which of the following statement is true?

Question 9 :
Assertion: In photoelectric effect, on increasing the intensity of light, both the number of electrons emitted and kinetic energy of each of them get increased but photoelectric current remains unchanged. Reason: The photoelectric current depends only on wavelength of light.

Question 10 :
The de-Broglie wavelength of an electron is the same as the wavelength of a photon. The K.E of photon is $'x'$ times the K.E of the electron,then $'x'$ is (m-mass electron ,h- planck's constant,c-velocity of light)

Question 11 :
Each question contains statement 1 and statement 2. Choose the correct answer (only one option is correct) from the following options.<br/>Statement -1 : In process of photoelectric emission, all emitted electrons do not have same kinetic energy.<br/>Statement -2 : If radiation falling on photosensitive surface of a metal consist of different wavelength then energy acquired by electrons absorbing photons of different wavelength shall be different.

Question 12 :
Assertion: When monochromatic light falls on a photosensitive material, the number of photo electrons emitted per second is $n$ and their maximum kinetic energy is $K_{max}$. If the intensity $I$ of the incident light is doubled, $n$ is doubled but $K_{max}$ remains the same. Reason: The value of $n$ is directly proportional to $I$ but $K_{max}$ is independent of $I$.

Question 13 :
De-Broglie wavelength of an electron accelerated by a voltage of 50 V is close to: $(|e|=1.6 \times 10^{-19} C, m_e=9.1 \times 10^{-31}kg, h=6.6 \times 10^{-34} Js).$&#160;