Samacheer Kalvi EM 12 Physics Vol2 Unit7 MCQs Mock Test

12th Physics - Volume 2 Mock Test

Unit 7: Dual Nature of Radiation and Matter

Choose the correct answer from the multiple choices, then click "Next" to goto next question and click "OK" after seeing the score.

 

1. The wavelength `\lambda_e` of an electron and `\lambda_p` of a photon of same energy E are related by __________ (NEET 2013)
   1.   `\lambda_p\propto\lambda_e`
   2.   `\lambda_p\propto\sqrt{\lambda_e}`
   3.   `\lambda_p\propto\frac1{\sqrt{\lambda_e}}`
   4.   `\lambda_p\propto\lambda_e^2`
2. In an electron microscope, the electrons are accelerated by a voltage of 14 kV. If the voltage is changed to 224 kV, then the de Broglie wavelength associated with the electrons would __________
   1.   increase by 2 times
   2.   decrease by 2 times
   3.   decrease by 4 times
   4.   increase by 4 times
3. A particle of mass `3\times10^{-6}g` has the same wavelength as an electron moving with a velocity `6\times10^6 m` `s^{-1}`. The velocity of the particle is __________
   1.   `1.82\times10^{-18}m` `s^{-1}`
   2.   `9\times10^{-2}m` `s^{-1}`
   3.   `3\times10^{-31}m` `s^{-1}`
   4.   `1.82\times10^{-15}m` `s^{-1}`
4. When a metallic surface is illuminated with radiation of wavelength λ, the stopping potential is V. If the same surface is illuminated with radiation of wavelength 2λ, the stopping potential is V/4. The threshold wavelength for the metallic surface is __________ (NEET 2016)
   1.   4λ
   2.   5λ
   3.   `\frac5{2}\lambda`
   4.   3λ
5. If a light of wavelength 330 nm is incident on a metal with work function 3.55 eV, the electrons are emitted. Then the wavelength of the emitted electron is (Take h=`6.6\times10^{-34}Js`)
   1.   < `2.75\times10^{-9}m`
   2.   ≥ `2.75\times10^{-9}m`
   3.   ≤ `2.75\times10^{-12}m`
   4.   < `2.5\times10^{-10}m`
6. A photoelectric surface is illuminated successively by monochromatic light of wavelength λ and λ/2. If the maximum kinetic energy of the emitted photoelectrons in the second case is 3 times that in the first case, the work function at the surface of material is (NEET 2015)
   1.   hc/λ
   2.   `\sqrt{\frac{6hv_o}m}`
   3.   `2\sqrt{\frac{hv_o}m}`
   4.   `\sqrt{\frac{hv_o}{2m}}`
7. In photoelectric emission, a radiation whose frequency is 4 times threshold frequency of a certain metal is incident on the metal. Then the maximum possible velocity of the emitted electron will be __________
   1.   `\sqrt{\frac{hv_o}m}`
   2.   `\sqrt{\frac{6hv_o}m}`
   3.   `2\sqrt{\frac{hv_o}m}`
   4.   `\sqrt{\frac{hv_o}{2m}}`
8. Two radiations with photon energies 0.9 eV and 3.3 eV respectively are falling on a metallic surface successively. If the work function of the metal is 0.6 eV, then the ratio of maximum speeds of emitted electrons will be __________
   1.   1 : 4
   2.   1 : 3
   3.   1 : 1
   4.   1 : 9
9. A light source of wavelength 520 nm emits `1.04\times10^{15}` photons per second while the second source of 460 nm produces `1.38\times10^{15}` photons per second. Then the ratio of power of second source to that of first source is __________
   1.   1.00
   2.   1.02
   3.   1.5
   4.   0.98
10. The mean wavelength of light from sun is taken to be 550 nm and its mean power is `3.8\times10^{26}` W. The number of photons received by the human eye per second on the average from sunlight is of the order of __________
    1.   `10^{45}`
    2.   `10^{42}`
    3.   `10^{54}`
    4.   `10^{51}`
11. The threshold wavelength for a metal surface whose photoelectric work function is 3.313 eV is
    1.   4125 Å
    2.   3750 Å
    3.   6000 Å
    4.   2062.5 Å
12. A light of wavelength 500 nm is incident on a sensitive plate of photoelectric work function 1.235 eV. The kinetic energy of the photo electrons emitted is be (Take h=`6.6\times10^{-34}Js`)
    1.   0.58 eV
    2.   2.48 eV
    3.   1.24 eV
    4.   1.16 eV
13. Photons of wavelength λ are incident on a metal. The most energetic electrons ejected from the metal are bent into a circular arc of radius R by a perpendicular magnetic field having magnitude B. The work function of the metal is __________ (KVPY-SX 2016)
    1.   `\frac{hc}\lambda-m_e+\frac{e^2B^2R^2}{2m_e}`
    2.   `\frac{hc}\lambda+2m_e[\frac{eBR}{2m_e}]^2`
    3.   `\frac{hc}\lambda-m_ec^2-\frac{e^2B^2R^2}{2m_e}`
    4.   `\frac{hc}\lambda-2m_e[\frac{eBR}{2m_e}]^2`
14. The work functions for metals A, B and C are 1.92 eV, 2.0 eV and 5.0 eV respectively. The metals which will emit photoelectrons for a radiation of wavelength 4100 Å is/are __________
    1.   A only
    2.   both A and B
    3.   all these metals
    4.   none
15. Emission of electrons by the absorption of heat energy is called __________ emission.
    1.   photoelectric
    2.   field
    3.   thermionic
    4.   secondary

Samacheer Kalvi EM 12th Std Physics Vol2 Unit7 MCQs Mock Test Instructions

Unit 7: Dual Nature of Radiation and Matter

Here you will find 15 MCQs questions and options. Read the questions carefully and select the appropriate answer for the question by selecting/clicking the box before the option. A pop-up box will open by displaying the result of the option selected. The result of each question will be based on percentages. Each question will have 3 chances to select the right option and for every chance, the percentage of scores will be reduced. Likewise, the remaining questions also take place. The overall percentage scored will be displayed at the completion of the mock test.

Note: Every time the page loads, the question and options will be randomized and takes you to the beginning of the particular exercise.

Button Navigations:

The Below Image shows the button navigations.

• The Home Button On the Top and Bottom Navigates to the Homepage of the Subject (Example: To Physics Vol2 if the mock test is taken from Physics Vol2).
• The Next Unit Button on the Top and Bottom Navigates to the Next Unit (Example: From Unit 7 to Unit 8 and so on).
• The Prev Unit Button on the Top and Bottom Navigates to the Prev Unit (Example: From Unit 7 to Unit 6 and so on).
• The Next Button next to the question numbers Navigates to the Next Question (Example: From 1 to 2 and so on).
• The Show All Questions Button Displays all the questions and options of that exercise on a single page.
• The Option Box Icon (Box with Question mark icon), is the box that is to be selected for the correct option. By selecting/clicking the option box, a pop-up box will open by displaying the result of the option selected.