| 1. |
Define 'electro chemical equivalent' of an element. |
1 |
| 2. |
Name a conductor disobeying Ohm's law. |
1 |
| 3. |
What amount of work would have to be done in bringing a test change ‘q' from
infinity along the perpendicular bisector of an electric dipole, up to a point
distant ‘r' from the centre of the dipole ? |
1 |
| 4. |
What is a ferromagnetic substance ? |
1 |
| 5. |
Define illuminating power' of a source of light. |
1 |
| 6. |
At what distance from the face should a plane mirror be held
so that a person of normal vision may see his/her own face most distinctly
in the mirror ? |
1 |
| 7. |
Half life of radium is 1600 years. In how many years
will an amount of radium reduce to 1/8 of its initial amount ? |
|
| 8. |
Write one property of X-rays that is applicable to medical
science. |
1 |
| 9. |
In one of Millikan’s oil-drop like experiment, an observer found the charges
of two oil drops to be 4.8 X 10-19 C and 8'0 x 1 0-19C. Find, from the
observation, the value of the electronic charge and the number of electrons in
the first
oil drop. |
½+1/2=1 |
| 10. |
What is a rectifier? |
|
| 11. |
Show that two electric lines of force can not
interact. |
2 |
| 12. |
What is 'lightning’ ? How can a tall building be saved
from the destructive action of lightning ? |
1+2+2 |
| 13. |
Show that a current loop is equivalent to a magnetic dipole.
|
2 |
| 14. |
What is induced e.m.f. ? How is it produced? |
1+1-2 |
| 15 |
Can sound waves pass through vacum ? Give reasons in support
of your answer. |
2 |
| 16 |
Show how you could convert a converging beam of light into a
parallel beam. |
2 |
| 17. |
Doppler's effect in light is symmetric. Justify the above
statement. |
2 |
| 18. |
An electric field is applied perpendicular to the
direction of a bunch of radio active radiations consisting of the three
types of radiations emitted from a source. Show, in a diagram how will the
radiations behave in presence of the electric field. |
2 |
| 19. |
Draw a neat is belled diagram to demonstrate photo
electric effect. |
2 |
| 20. |
How are an ammeter and a voltmeter to be connected in
an electrical circuit ? Why should an ammeter have a low resistance while a
voltmeter, a high resistance. |
½+1/2+1+1=3 |
| 21. |
How long will an electric kettle marked 500W-230V take
to boil 1 litre of water initially at 200C, assuming that 20% of the
electric energy goes waste ? |
3 |
| 22. |
Prove that light waves are transverse. |
3 |
| 23. |
An instantaneous A. C. voltage is given by, E=10 sin (100?)t, where 'E' is
in volts and 't’ is in second.Find the
(i) peak value and
(ii) virtual value of the instantaneous voltage.
Find also the time period of the Oscillatory A. C. |
1+1+ 1= 3 |
| 24. |
Show that an observer under water of refractive index n, at a depth h,
looking Possibly upwards will see a circular hole of area ph2/n2-1 on the
surface of the water,through which the observer will be able to see the outside world. |
3 |
| 25. |
What amount of energy will be absorbed or liberated when an electron in the
L-shell jumps to the K-shell in Bohr's model of atomic structure?
(Energy of the ground state of hydrogen atom= 13'6eV). |
3 |
| 26 |
Find an expression for the electric potential at a point in a medium of
specific inductive capacity K due to a point charge.
Hence deduce an expression for the electric field intensity
due to the point charge at the same point.
OR
Deduce an expression for the energy of a charged
capacitor. In what form is the energy stored in the capacitor ? |
3+2=5 |
| 27. |
Derive an expression for the force experienced by a current carrying
conductor in a magnetic field.
For what angle of orientation of the conductor to the magnetic field, will
the force be maximum ?
OR
What is Blot -Savart's law of magnetic effect of electric
,current ? Deduce from the law, the definition of 1Tesla. |
4+1=5 |
| 28. |
What is alternating current ? How is it generated ? In A.C. circuit, what
substitutes the
ohmic resistance in D.C. circuit ?
Why is it not possible to measure A.C. by a D.C. ammeter ?
OR
Describe the construction and action of an electrical machine in which
electrical energy is transformed into mechanical energy. |
1+1+1+2=5 |
| 29. |
Describe the electronic bard theory of a crystalline solid.
OR
Describe how N-type and P-type semiconductors are formed. Name the dopant and
majority carrier in each type of semiconductors you describe.
|
5 |
| 30. |
Three equal resistances 6 Ohm each are connected to form the sides of an
equilateral triangle. The resistance between any two terminal vertices is
(a) 18 ohm
(b) 9 ohm
(c) 4 ohm
(d) 2 ohm.
|
1 |
| 31. |
A small needle of iron is suspended freely in the
magnetic field of a bar magnet, The needle will experience
(a) a torque but no net force
(b) a net force but no torque
(c) both torque and net force
(d) neither torque nor net force |
1 |
| 32 |
Twilight is caused by the phenomenon of
(a) diffraction
(b) interference
(c) polarisation
(d) Scattering of light. |
1 |
| 33. |
For two different positions of an object, images of the same magnification
can be produced by
(a) a convex mirror only
(b) a concave mirror only
(c) both convex and concave mirrors
(d) none of convex and concave mirross.
Given, m0= 4px 10-7 TmA-1 |
1 |
