Cbse Class 12 Sample PapersCbse Class 12 Sample PapersSAMPLE PAPER PHYSICS
1. Why a D.C voltmeter and D.C ammeter cannot read alternating current?
2. What is the electrostatic potential due to an electric dipole at an equatorial point? Is their a electric
3. An electron does not suffer any deflection while passing through a region of uniform magnetic field.
What is the direction of the magnetic field?
4. A convex lens is placed in water. Will the focal length change? Explain
5. The electric field between two parallel plates of capacitor changes with time, a current begins to flow
in between the plates. Write the related law.
6. The stopping potential in an experiment on photoelectric effect is 1.5 V. What is the maximum
kinetic energy of the photo electrons emitted? Know More About :- Cbse Previous Year Question Paper BoB ao ra dr s.s EduEd ru ir tet .e c. oc mPage : 1/3
7. When 3 7Li is bombarded with a certain particle, two alpha particles are produced .Identify the
8. Draw the diode circuit of OR gate.
9. Define electric flux. Write its SI unit. A charge q is enclosed by a spherical surface of radius R. If the
radius is reduced to half, how would the electric flux through the surface change?
10. The given graph shows the variation of charge q versus potential difference V for two capacitors.
The two capacitors C1 and C2 have same plate separation but the plate area of C2 is double than that of
C1. Which of the lines in the graph correspond to C1 and C2 and why?
11.In a meter bridge balance point is found at a distance l1 with resistances R and S as shown in figure.
When an unknown resistance X is connected in parallel with resistance S, the balance point shifts to a
distance l2. Find the expression for X in terms of l1, l2 and S.
12. Define current sensitivity and voltage sensitivity of a galvanometer. Increasing the current
sensitivity may not necessarily increase the voltage sensitivity of a galvanometer. Justify.
13. When 100 volts d.c is applied across an inductor, a current of 1A flows through it. If the same
inductor is connected across 100 v a.c. source, a current reduces to 0.5 A. Why is the current reduced in
later case? Calculate the reactance.
14. Write two characteristics of a transformer. Diagrammatically represent step-up and step-down
16. A radioactive isotope has a half life of T years. How long will it take the activity to reduce to (i)
3.125 % and ii) 1 % of its original value?
17. Write the function of (i) Transducer and (ii) Repeater in the context of communication system. Read More About :- Icse Sample Paper BoB ao ra dr s.s EduEd ru ir tet .e c. oc mPage : 2/3