CBSE Class 12 Physics Question Paper 2007 (3)

CBSE Class 12 Physics Question Paper 2007 (3). Students can download the last year question papers using the link below. Free download of examination question papers with solutions.Last 10 year question papers should be practised to get better marks in examinations.

1. In a series LCR circuit, the voltages across an inductor, a capacitor and a resistor are 30 V, 30 V and 60 V respectively. What is the phase difference between the applie  voltage and the current in the circuit ? 

2. Ultraviolet radiations of different frequencies and are incident on two photosensitive materials having work functions and respectively. The kinetic energy of the emitted electrons is same in both the cases. Which one of the two radiations will be of higher frequency ?

3. Define the term 'activity' of radionuclide. Write its SI unit. 

4. An electron is moving a along +ve x-axis in the presence of uniform magnetic field along +ve y-axis. What is the direction of the force acting on it ? 

5. What should be the length of dipole antenna for a carrier wave of frequency ?

6. Two point charges and are separated by a distance of 1 m in air. Calculate at what point on the line joining the two charges is the electric potential zero. 

7. A voltage of 30 V is applied across a carbon resistor with first, second and third rings of blue, black and yellow colours respectively. Calculate the value of current, in mA, through the resistor. 

8. A galvanometer has a resistance of It gives full scale deflection with a current of 2 mA. Calculate the value of the resistance needed to convert it into an ammeter of range 0-0.3 A. 

9. Calculate the current drawn by the primary of a transformer which steps down 200 V to 20 V to operate a device of resistance . Assume the efficiency of the transformer to be 80%.

Please click the link below to download pdf file of CBSE Class 12 Physics Question Paper 2007 (3).