PHYSICS 2005 (Set II—Outside Delhi)
Except for the following questions all the remaining questions have been asked in Set I..
Q. 1. What should be the length of a dipole antenna for a carrier wave of frequency 6 x 108 Hz? 1
Q. 2. Show graphically how the stopping potential for a given photosensitive surfa- ce varies with the frequency of the incident radiation. 1
Q. 3. In a series LCR circuit, the voltage across an inductor, capacitor and resistor are 20 V, 20 V and 40 V respectively. What is the phase difference between the applied voltage and the current in the circuit? 1
Q. 4. Under what condition does an electron moving through a magnetic field experience maximum force? 1
Q. 5. How does the coulomb force between two point charges depend upon the dielectric constant of the intervening medium? 1
Q. 10. Establish a relation between current and drift velocity. 1
Q. 11. A charge q is Placed at the centre of the line joining two equal charges Q. Show that the system of three charges will be in equilibrium if q = - Q/4. 2
A 5 capacitor is charged by a 100 V supply. The supply is then disconnected and the charged capacitor is connected to another uncharged 3 capacitor. How much electrostatic energy of the first capacitor is lost in the process of attaining the steady situation?
Q. 13. The potential difference across the terminals of a battery of emf 12 V and internal resistance 2 ohm drops to 10 V when it is connected to a silver voltameter. Calculate the silver deposited at the cathode in half an hour. Relative atomic mass of silver is 108. 3
Q. 15. Define mutual inductance and give its S. I . unit. Derive an express on for the mutual inductance of two long coaxial solenoids of same length wound one over the other. 3
Q. 17. A double convex lens made of glass of refractive index 1.6 has its both surfaces of equal radii of curvature of 30 cm each. An object of 5 cm height is placed at a distance of 12.5 cm from the lens. Find the position, nature and size of the image. 3
Physics 2005 Question Papers Class XII
CBSE 2005 Question Papers Class XII