Question Pool Electrostatic Potential and Capacitance

Electrostatic Potential and Capacitance - SAMAGRA Question Pool & Answers | Class 12

Kerala Syllabus SAMAGRA SCERT SAMAGRA Question Pool for Class 12 Physics Electrostatic Potential and Capacitance

BrainsPrep Logo


Qn 1.
If the distance between the plates of a capacitor is halved then what happens to its capacitance?


Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 2.

Why is it safer to be inside a car than standing under a tree during lightning?



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 3.

A parallel plate capacitor has plates of area 200 cm2 and separation between the plates 1 mm. Calculate (i) the potential difference between the plates if 1n C charge is given to the capacitor (ii) with the same charge (1n C) if the plate separation is increased to 2 mm, what is the new potential difference and (iii) electric field between the plates.



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 4.

Define electric potential difference between two points ?



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 5.

“Electric potential at a point is 5 volt” .what do you mean by the statements ?



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 6.

Give the unit and dimensions of electric potential



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 7.

If " W  " is the work done to bring a charge " q " from infinity to a point then what is the electric potential at that point ?



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 8.

What do you meant by electric potential at a point ?



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 9.

What is meant by equipotential surface?



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 10.

Inside a hollow charged spherical conductor, the potential

A) Is constant

B) Varies directly as the distance from the centre

C) Varies inversely as the distance from the centre

D) Varies inversely as the square of the distance from the centre

 



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 11.

Two electrons are held 3μm apart. When released from rest, what is the velocity of each electron when they are 8μm apart?



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 12.

The distance AB between charges Q1 and Q2 shown below is 5.0 m. How much work must be done to move charge Q2 to a new location at point C so that the distance BC = 2.5 m?

                                                                                                  

                 



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 13.

Draw the equipotential surface in a uniform electric field?



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 14.

Draw the equipotential surface for two like charges separated by a small distance ?



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 15.

Draw the equipotential surface for an electric dipole?

 



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 16.

Draw the equipotential surface for a point charge?



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 17.

Write the expression for the potential at a point on the surface of

i) the inner sphere and

ii) the outer sphere.

                                      



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 18.

a) What is the use of van de Graff generator?

b) States the principle of van de Graff generator?

c) Explain its working with a neat diagram ?



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 19.

State the principle/s of van de Graff generator?



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 20.

a) Find the work done to assemble two charges q1 and q2 at the points of potentials V(r1) and V(r2) respectively?

b) If there is no external electric field what is the work done to separate them far apart.


 



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 21.

An electric dipole is placed in a uniform electric field at an angle θ with the field E.

a) What happens to the dipole

b) Obtain the expression for energy of the above system.

c) Give the conditions for stable and unstable equilibrium of the dipole system.



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 22.

N identical and equally charged (q) liquid drops coleases to form a single big drop .What is the charge and capacitance of the big drop. ?



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 23.

a)Define electric polarization and give its unit ?

b)Writes the relation between polarization and electric field ?



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 24.

Distinguish between polar and non polar dielectrics with examples?

 



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 25.

The work done to move half a revolution of electron in an Orbit is zero. Why?



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 26.

Prove that electric field is always perpendicular to an equipotential surface.

Work done to move a charge q from one point to another point on an equipotential is zero.



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 27.

a)What do you meant by energy of a system of three charges ?

b)obtain the expression for the potential energy of the above system of charges?



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 28.

a)What do you meant by energy of a system of two charges ?

b)obtain the expression for the potential energy of a system of two charges?



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 29.

what are the different methods to increase the capacitance of a parallel plate capacitor.



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 30.

a)What is the use of a capacitor ?

b)Obtain the expression for the capacitance of a parallel plate capacitor ?

c)What are the methods to increase the capacitance of a parallel plate capacitor ?



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 31.

Where does the energy stored in a capacitor ?

 



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 32.

When a dielectric slab is introduced between the plates of a capacitor what happens to its capacitance ?



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 33.

When a dielectric is introduced between the plates of a charged but source less parallel plates capacitor then what happens to the electric field between the plates ?



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 34.

Define one Farad ?



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 35.

Give the unit and dimensions of capacitance ?

 



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 36.

Find the resultant capacitance when three capacitors of capacitance C1 ,C2 and C3 are connected in series ?

 



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 37.

You are provided with three capacitors of capacitance C1, C2 and C3. How will you connect them to get maximum capacitance. Obtain the expression for total capacitance of the combination.


 



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 38.

a) obtain the expression for the potential due to a electric dipole at any point.

b) what is the potential at a point on the axial and equatorial lines of the dipole.



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 39.

a) what do you mean by energy of a capacitor

b) obtain an expression for energy stored in a capacitor.

c) a capacitor is charged and disconnected from the cell and a dielectric slab is introduced between the plates of the capacitor what happens to the energy of the capacitor and why?



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 40.

What is the work done by the field of a nucleus in a complete circular orbit of the electron? What if the orbit is elliptical?Justify your answer.



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 41.

In a Van de Graaff type generator a spherical metal shell is to be a 15 × 106 V . The dielectric strength of the gas surrounding the electrode is 5 × 107 Vm−1. What is the minimum radius of the spherical shell required?



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 42.

Describe schematically the equipotential surfaces corresponding to

(a) a single positive charge at the origin, and

(b) a uniform grid consisting of long equally spaced parallel charged wires in a plane.


 



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 43.

Describe schematically the equipotential surfaces corresponding to

(a) a constant electric field in the z-direction,

(b) a field that uniformly increases in magnitude but remains in a constant (say, z) direction,



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 44.

A bird perches on a bare high power line, and nothing happensto the bird. A man standing on the ground touches the same line and gets a fatal shock. Why?



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 45.

Ordinary rubber is an insulator. But special rubber tyres of aircraft are made slightly conducting. Why ?


 



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 46.

A comb run through one’s dry hair attracts small bits of paper.Why? What happens if the hair is wet or if it is a rainy day?



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 47.

Prove that electric field at the surface of a charged conductor, 



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 48.

Vehicles carrying inflammable materials usually have metallic ropes touching the ground during motion. Why?



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 49.

Does the kinetic energy of a small negative charge increase or decrease in going from Q to P ?

                     


Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 50.

Does the kinetic energy of a small negative charge increase or decrease in going from B to A?

                                  


Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 51.

Give the sign of the work done by the external agency in moving a small negative charge from B to A ?

                                


Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 52.

Give the sign of the work done by the field in moving a small positive charge from Q to P.

                               


Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 53.

Give the sign of the potential energy difference of a small negative charge between the points A and B ?

                                

 



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 54.

Chose the correct one from the following ?Give reason.

                                    A                         B                           C                

 

a) VA<VB<VC                      b) VA >VB >VC

c) VA =VB=VC                      c) VA<VB>VC


 

 



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 55.

Give the sign of the potential energy difference of a small negative charge between the points Q and P ?

                                 



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Qn 56.

A molecule of a substance has a permanent electric dipole moment of magnitude 1029 C m. A mole of this substance is polarised (at low temperature) by applying a strong electrostatic field of magnitude 106 V m1. The direction of the field is suddenly changed by an angle of 60º. Estimate the heat released by the substance in aligning its dipoles along the new direction of the field. For simplicity, assume 100% polarisation of the sample.?



Download BrainsPrep

Get Free Study Materials + 1 Week Free Trial of BrainsPrep Class 12 Tuition


BrainsPrep Logo
Class 10 English Medium SAMAGRA Question Pool Click here
Class 10 - Malayalam Medium SAMAGRA Question Pool Click here
Class 9 English Medium SAMAGRA Question Pool Click here
Class 11 SAMAGRA Question Pool Click here
Class 12 SAMAGRA Question Pool Click here
BrainsPrep Logo