www.nvsrochd.gov.in Model Question Paper Plus Two, 12th Std, +2, Hsc Navodaya Vidyalaya Samiti : Physics

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SAMPLE PAPER 2011
CLASS - XII
SUBJECT- PHYSICS
Time Allotted: 3hrs. Max. Marks : 70

http://nvsrochd.gov.in/
http://nvsrochd.gov.in/S_club/phy/guess%20paper%202.doc

General Instructions:
1.All questions are compulsory.
2.There are 30 questions in total. Questions 1 to 8 carry one mark each, questions 9 to 18 carry two marks each, questions 19 to 27 carry three marks each and questions 28 to 30 carry five marks each.
3.There is no overall choice. However, an internal choice has been provided in one question of two marks, one question of three marks and all three questions of five marks each. You have to attempt only one of the given choices in such questions.
4.Use of calculators is not permitted.
5.You may use the following physical constants wherever necessary :
c = 3 x 108ms-1
h = 6.6 x 10-34Js
e = 1.6 x 10-19 C
µo?= 4? x 10-7A-1 m T
Boltzmann constant k = 1.38 x 1023 JK-1
Avogadro’s number NA = 6.023 x 1023/mole
Mass of neutron mn = 1.6 x 10-27 kg

1.An electron an a proton, having equal momenta, enter a uniform magnetic field at right angles to the field lines. What will be the ratio of the radii of curvature of their trajectories?

2.Name the device which shows the variation of current (I) with voltage (V) as shown:
Also mention any one application of the device.

3.Hertz observed, during the experiment to produce e.m.waves, an ‘enhancement’ in the sparks across the detector loop when the emitter plate was illuminated by U.V radiations. What was it due to?1

4.Define ‘trans-conductance’ of a transistor. 1

5.When current in a coil changes with time, how is the back emf induced in the coil related to it? 1

6.A parallel beam of monochromatic light falls normally on a single narrow slit. How does the angular width of the principal maximum in the resulting diffraction pattern depend on the width of the slit?1

7.What is the mathematical relation between speed of electromagnetic waves, permittivity and permeability in vacuum?

8.Two point charges q1 and q2 are placed close to each other. What is the nature of the force between them when: (i) q1q2 < 0 and (ii) q1q2 >0? 1

9.A message signal of frequency 10 kHz and peak voltage of 10 volts is used to modulate a carrier of frequency 1 MHz and peak voltage of 20 volts. Determine:
(a) modulation index,
(b) the side bands produced.2

10.Derive an expression for the potential at the point on the axial line of an electric dipole.