PSEB CBSE TERM-2 EXAM: MODEL QUESTION PAPER PHYSICS 10+2
CLASS--XII PHYSICS
TERM-II Time : 2 Hours Max, Marks : 35
Note:
1. Question paper has total 17 questions.
2. All questions are compulsory.
3. Q.1-5 will carry 1 mark each.
4. Q.6-13 will carry 2 mark each. there will be internal choice in two questions.
5. Q.14-16 will carry 3 mark each. there will be internal choice in two questions.
6. Q 17 will be of 5 marks, there will be internal choice in it.
SECTION A
1. The phenomenon of splitting up of white light into its constituent colours is called ...... of light.
2. Power of a lens will be more in air than water. (True /False)
3. What is rest mass of photon?
4. What is the principal of nuclear bomb?
S. What is fermi level?
SECTION B
6. What is the critical angle for a material of refractive index √2
Or
Explain, why white light is dispersed when passing through a prism.
7. Why is wave nature of matter not apparent in our daily observations?
8. Obtain de Broglie equation for a material particle.
Or
Find the momentum of an X-ray photon of wavelength 𝞴.
9. Define nuclear force. Give any four properties of nuclear force.
10. Distinguish between Nuclear fission and Nuclear Fusion.
11. Define atomic mass unit. Show that 1 amu =931.5 MeV.
12. What do you mean by hole in a semiconductor ? Write its three characteristics.
13. What arc the essential characteristics of a semiconductor ?
SECTION C
14. The refractive index of material of an equi-double convex lens is 1.5. What is its focal length? (given radius of curvature R
Q15. Deduce the relation N = N₀ `e^{-λt}`, where symbols have their usual meanings.
OR
Define the term decay constant and half-life of a radio-active sample. Derive a relationship between decay constant and half-life of a radioactive sample.
16. What is rectification ? Explain with the help of a circuit diagram, how a junction diode acts as a full-wave rectifier
SECTION D
17. State new cartesian sign conventions. Derive the expression
When refraction occurs from rarer to denser medium at convex spherical refracting surface (𝜇₂<𝜇₂)
OR
Derive an expression for the refractive index of the material of a prism in term angle of prism and the angle of minimum deviation
