#### 12th Standard English Medium Physics Reduced syllabus Creative two mark Question with Answerkey - 2021(Public Exam )

12th Standard

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Physics

Time : 01:00:00 Hrs
Total Marks : 50

2 Marks(Creative)

25 x 2 = 50
1. When does a dielectric said to be polarized?

2. What is the electric flux through a cube of side 1cm which encloses on electric dipole?

3. What orientation of an electric dipole in a uniform electric field corresponds to its
(i) stable and
(ii) unstable equilibrium? Depict the orientations.

4. Two isolated metal spheres A &B have radii R & 2R respectively and same charge q. Find which of the two spheres have greater energy density just outside the surface of the sphere.

5. The electric field due to a point charge depends on the distance r as parallely indicate how each of the following quantities depends on r?
a. Intensity of light from a point source.
b. Electrical potential due to a point charge.
c. Electrical potential at a distance r from to centre of a charged metallic sphere Given r < radius of the sphere.

6. The graph shown here shows the variation of total energy (E) stored in a capacitor against the value of the capacitance (c) itself. Which of the two is kept constant for this graph, whatever the charge an capacitor of the potential used to charge it?

7. A parallel plate capacitor of capacitance C is charged to a potential V. It is connected to another uncharged capacitor having the same capacitance find the ratio of the energy stored in the constance to that stored initially in the single capacitor.

8. Define the term electric power and circuit its SI unit.

9. Define electric energy state its commercial units.

10. What is meant by Heating effect of electric current?

11. What happens to the drift velocity of electron and to the resistance if length of conductor and to the resistance if length of conductor unchanged?

12. Plot a graph showing the variation of circuit I various resistance R connected to a cell of emf E and internal resistance r.

13. State Right hand thumb rule.

14. Explain the use of transformers in long distance transmission of electric power

15. Does the current in an a.c circuit lag lead or remain in phase with the applied voltage. When
(i)  γ =  γr
(ii)  γ <  γr
(iii)  γ >  γr
Where  γr is the resonant frequency?

16. (i) How is the speed of Electromagnetic waves in vacuum determined by the electric and magnetic fields? and
(ii) Do Electromagnetic waves carry energy and momentum?

17. Write the two conditions for total internal reflection.

18. A convex lens (n = 1.5) of focal length fs immersed
(I) in water n = 1.33 and
(ii) in carbon disulphide n = 1.6, how does the lens behave in the two cases?

19. If the intensity of radiation in a photocell is increased how does the stopping potential
vary?

20. A fusion reaction is more energetic than a fission reaction. Why?

21. Define nano science.

22. How does the fringe width of interference fringes change, when the whole apparatus Young's experiment is kept in water (refractive index4/3)?

23. Define conduction band.

24. Define Zener effect

25. Write the function of Repeater.