CBSE Physics  Sample Paper 1998 
(Delhi) Part - 2

 

Set - 1

Q. 1. What is the work done in moving a charge of 10 NC between two points on equipotential surface ?

 

Q. 2. Name the device used for measuring the internal resistance of a secondary cell. 1

 

Q. 3. What is the nature of the magnetic field in moving coil galvanometer ? 1

 

Q. 4. If a rate of change of current of 2 A s^-1 induces an e.m.f. of 10 mV in a solenoid, what is the self-inductance of the solenoid ? 1
 

 

Q. 5. What type of magnetic material is used in making permanent magnets ? 1
 

 

Q. 6. Two metals A, B have work-function 2eV, 4eV respectively. Which metal has a lower threshold wavelength for photoelectric effect ?
 

 

Q. 7. Which has more ionising power  alpha or beta particles ? 1
 

 

Q. 8. Which part of the electromagnetic spectrum is used in operating RADAR ? 1
 

 

Q. 9. Which type of biasing gives a semiconductor diode very high resistance ?
 

 

Q. 10. How is luminosity of the star is related to its radius ?
 

Set - 2

 

Q. 1. In parallel plate capacitor, the capacitance increases from 4µF to 80µF on introducing a dielectric between the plates. What is the dielectric constant of the medium ?
 

 

Q. 2. Give reasons as to why electrical conductance of electrolytes is less than that of metals.
 

 

Q. 3. How does the intensity of magnetisation of paramagnetic material vary with increasing magnetic field ?
 

 

Q. 4. The instantaneous current from A.C. source is / = 5 sin 314t. What is the r.m.s. value of the current ? 1
 

 

Q. 5. Why is the transmission of signals using ground waves restricted to frequencies less than about 1,500 kHz? 1
 

 

Q. 6. Draw a p-n junction with reverse bias. 1
 

 

Q. 7. If maximum kinetic energy of electrons emitted by a photo cell is 4eV, what is the stopping potential ?
 

 

Q. 8. What causes the tail of a comet when the comet passes close to the sun ?
 

 

Q. 9. Write any one equation representing nuclear fusion reaction.
 

 

Q. 10. What is the nature of the magnetic Held in a moving coil galvanometer ? 1
 

 

Q. 11. The electric field due to a point charge is 20 NC^-1 and electric potential at that point is 10 JC^-1 . Calculate the distance of the point from the charge and magnitude of the charge.
 

 

Q. 12. In the following circuit, a metre bridge is shown in its balanced state. The metre bridge has a resistance of 1 ohm cm^-1. Calculate the value of unknown resistance X and the current drawn from the battery of negligible resistance. 2
 

 

Q. 13. Calculate the electrical conductivity of the material of conductor of length 3m, area of cross-section 0.02 mm² having a resistance of 2 ohm.
 

 

Q. 14. Define self-inductance. Write down the expression for the sell-inductance of a long solenoid of length /. 2
 

 

Q. 15. A T.V. tower has a height h. Derive an expression for the maximum distance upto which the signals can be received on the earth. 2
 

 

Q. 16. How can one distinguish between unpolarized and a linearly polarized light beam using polaroid ?