CBSE Class 12 Physics Sample Paper 2014 Set 04

1. The magnetic field lines form closed curves. Why? 

2. What is band pass filter. 

3. How does magnifying power of a microscope change on decreasing the aperture of its objective? 

4. Name the part of Electimagnetic spectrum which is suitable for (i) Physical therapy (ii) TV communication. 

5. Why is energy distribution of β ray continuous? 

6. A point source of light is at the focus of a convex lens. What is the type of refracted wavefront? 

7. Drawn a graph showing variation of de Broglie wavelength of an electron with the variation of its momentum 

8. All the cells are identical each of emf E and internal resistance ‘r’. What is the current passing through R. 

9. What is a repeater? Explain with the help of a diagram. How does it increase the communication range. 

10. In a wire connected across a source, drift speed and electric field are v and E respectively. The wire is stretched uniformly of double the length, what will be new (i) drift speed (ii) electric field. 

11. Sketch the output wave form from an OR gate. The input A and B are shown in the figure. If the output of above OR gate is fed to a Not gate, name the gate so formed. 

12. A charged particle of charge q and mass m is accelerated through potential different V befor entering a magnetic field B, perpendicular to the direction of motion. What will be the radius of circular path 

OR

A circular coil of radius r is carrying current I. at what distance from the centre of loop on the axis magnetic field is one eight the magnetic field at the centre.

13. P and Q are long straight conductors r distance apart. N is a point in the plane of wires 4 distance away from P carrying current I. What is the magnitude and direction of current in the wire Q, so that net magnetic field at N is zero.

14. In an electiomagnetic wave propagating along + x-axis electric field vector  is Ey = 4 x 10³ Cos (3 x 10⁸ t – 1.5 x) V/m. What is (i) the frequency of emwave (ii) amplitude of magnetic field.

15. A and B are two concentric metallic spherical shell of radii a and b having charge q and Q respectively. How much work will be done in moving a test charge q₀ from A to B (a < b). 

Please refer to attached file for CBSE Class 12 Physics Sample Paper 2014 Set D