CBSE Physics Sample Question Paper : Set-10
Q. I. State one basic property of electric charge.
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Q. 2. How much current be passed through a long wire so that it produces a magnetic field of 1 testa at a distance of 10 cm from it?
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Q. 3. What types of charge carriers are there in a p-type semiconductor?
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Q. 4. What is the dynamic mass of a photon of frequency v?
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Q. 5. Write two conditions for the existence of atmosphere on a planet.
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Q. 6. Which type of biasing results in very high resistance of a p-n junction diode? Draw a diagram showing this bias.
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Q. 7. What is the energy associated in joules with a photon of wavelength 4000 A?
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Q. 8, On what factors the number of radioactive nuclei which undergo decay depend?
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Q. 9. Differentiate between radiant flux and luminous flux.
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Q. 10. Why is plane current loop considered a magnetic dipole?
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Q. 11. A 1.5 µF capacitor has a capacitive reactance of 6Ω what is the frequency of the source? If the frequency of the source is doubled, what will be the capacitive reactance?
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Q. 12. What are Fraunhofer lines? How are they produced?
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Q. 13. A proton moves with a speed of 7.45 x 105 ms-1 directly towards a free proton originally at rest Find the closest distance for the two protons, (mass of proton = 1.66 x 10-27 kg).
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Q. 14. What is Green house effect for the atmosphere of the earth and what is its importance? Draw a labelled diagram in support of your answer.
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Q. 15. Derive the expression for the electric potential at a distance V from a point charge ‘q’.
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Q. 16. Give the name of the source and the spectral range of the following wavelength: 6000 A Å 200 m, 0.5 Å and 1200 Å.
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Q. 17. Assuming the diameter of the eye pupil to be 2.0 mm, calculate die smallest angular separation at which two point objects can be distinctly seen when viewed in light of wavelength 6000 Å.
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Q. 18. Explain emission of gamma rays with an example.
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Q. 19. (a) How can the value of Plank’s constant be determined from the experiments of photoelectric effect?
(b) Photon is a zero-mass particle, explain briefly.
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Q. 20. If photo electrons are to be emitted from a potassium surface with a speed of 6 x 105 ms-1 what frequency of radiation must be used? (Threshold frequency for potassium is 4.22 X 1014 Hz, h = 6.6 X 10-34 Js and me = 9.1 x 10- 31 kg).
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Q. 21. How is the depletion region formed in a p-n junction diode?
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Q. 22. Derive an expression for the magnetic field on the axis of a toroidal solenoid.
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Q. 23. Draw a labelled diagram of Geiger-Marsden experiment on the scattering of α-particles. How is the size of nucleus estimated in this experiment?
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Q. 24. Describe how spectrometer can be used to obtain pure spectrum.
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Q. 25. A magnet suspended at 30° with the magnetic meridian makes an angle of 45° with the horizontal. What is the actual value of the angle of dip?
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Q. 26. Explain the phenomenon of hysterisis in ferromagnetic materials.
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Q. 27. An 80 V, 800 W heater is to be operated on a 100 V, 50 Hz supply. Calculate the inductance of the choke required.
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Q. 28. (a) Prove mathematically that the average value of alternating current over one complete cycle in zero.
(b) A series LCR circuit consists of a resistance of 10 Q., a capacitor of reactance 60 Q and an inductor coil. The circuit is found to resonate when put across 300 V, 100 Hz supply. Calculate
(i) the inductance of the coil
(ii) current in the circuit at resonance.
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Q. 29. Derive an expression for the resistivity of a were in terms of its material parameters—number density of free electrons and collision time.
You are required to determined the specific resistance of the material of a wire in the laboratory. Draw the circuit diagram. Explain the principle of experiment. Give the formula used.
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Q. 30. What are secondary cells? Explain in brief the charging and discharging of a lead accumulator.
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