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what is the meaning of quantisation of charge?
state any two postulates of bohr's theory of hydrogen atom. what is the maximum possible number of spectral lines observed when hydrogen atom is in its second excited state. justify your answer. calculate ratio of the maximum and minimum wavelength of the radiations emitted in this process.
Difference between gravitational force and electrostatic force
what is the dimensional formula of epsilon not?
Two similarly and equally charged identical metal spheres A and B repel each other with a force of 0.000002 N. A third identical sphere C is touched with A and then placed at the mid point between A nd B. What is the net electric force on C?
Two charges,one +5 microcoulomb and other of -5microcoulomb are placed 1mm apart .Calculate the dipole moment
( ans 5*10 to the power -9 Cm)
Three point charges of +2 microcoulomb,-3 microcoulomb and -3 microcoulomb are kept at the vertices A,B and C respectively of an equilateral triangle of side 20 cm.What should be the sign and magnitude of the charge to be placed at the mid point(M) of side BC so that the charge at A remains in equilibrium?
what is N=nNa
A charge q is placed at the center of the line joining two equal charges Q. Show that the system of three charges will be in equilibrium if q = -Q/4.
derive an expression for potential energy of an electric dipole in a uniform electric field .
An infinite number of charges each equal to q are placed along x axis at x=1 , x=2 , x=4, x=8 and so on . Find the electric field at the point where x=0 due to this setup of charges and what will be the electric field if inthe above setup the consecutive charges have opposite sign.?
Explain the formulae E = Sigma / Epsilon not.
E is the electric field vector.
Epsilon not is the specific inductive capacity or relative permittivity of vaccum.
Sigma = ? (doubt)
what does q1+q2 =0 signify in electrostatics?
difference between uniform and non-uniform electric fields.... plzz if possible draw diagrams too..!
a gas is heated through 1 degree celsius in a closed vessel. its pressure is increased by 0.4%.the initial temperature of the gas is ????
A stream of electrons travelling with speed of v m/s at right angles to a uniform electric field E is deflected in a circular path of radius r.Prove that e/m =v2 /rE ?
A charge "q" is placed at the centre of the cube of side "l". What is the electric flux passing through each face of the cube?
Pls provide chart for values of Sin, Cos, Tan and Cot for specific values from 30 degrees to 360 degrees.
 What is quantisation of charge?
What are the limitations of Coulomb's Law ?
if a point charge be rotated in a circle of radius r around a charge q ,what will be work done ?
A pendulum bob of mass of 80 mg and carrying a charge of 2 X 10-8 C is at rest in a horizontal uniform electric field of 20,000 V/m. Find the tension in the thread of the pendulum and the angle it makes with the vertical.
Take( g = 9.8ms-2 )
Four charges, each equal to Q are placed at the 4 corners of a square and a charge q is placed at the centre of the square. If the system is in equilibrium, then the value of q is?
what is the least possible value of electric charge?
two equal point charges A and B are R distance apart. A third point charge placed on the prependicular bisector at a distance 'd' from the center will experience maximum electrostatic force when
1. d = R/2 X 1.414
2 d = R/ 1.414
3. d = R 1.414
4. d = 2 X 1.414 R
name the system for which electric field at distances 1cm,2cm,3cm are in the ratio 1:1/8:1/27
Three charges each equal to q are placed at the three corners of a square of side a. Find the electric field at the fourth corner.
Electric field strength, E=V/r what is V and r
when a body becmes negatively charged , its mass
[a] decreases [b] increases
[c] remins the same [d] none of these
q. Two point charges of +16 micro coulomb and -9 micro coulomb are placed 8 cm apart in air .Determine the position of the point at which the resultant field is zero .
Two small balls having equal positive charge q coulomb are suspended by two insulating strings of equal length ' l ' meter from hook fixed to stand.The whole setup is taken in a satellite into sapce where there is no gravity. What is the angle between the two strings and the tension in each string?
an electric dipole of dipole moment 20 *10-6Cm is enclosed by a closed surface .what is the net flux coming out of the surface?
2 point charges at distance ' r ' in air exert a force ' F ' on each other, at what distance will these charges experience the same force ' F' in a medium of dielectric constant K?
two fixed point charges +4e and +e units are separated by a distance a .where should the third point charge be placed for it to be in equilibrium ?
how much positive and negative charge is there in a cup of water
Two infinitely long parallel wires having linear charge densities λ1 and λ2 respectively are placed at a distance of R metre. The force per unit length on either wire will be.......?
what is the direction of electric field at the surface of a charged conductor having charge density σ < 0.
what is the principle of vernier calipers
why do electrostatic experiments not work well on humid days
electrostatic field lines cannot be discontinuous why?
An electron falls through a distance of 1.5 cm in a uniform electric field of magnitude 2.0 × 104 N C–1 in the direction of the field . Then the direction of the field is reversed keeping its magnitude unchanged and a proton falls through the same distance . compute the time of fall in each case.
state Gauss' law in electrostatics.
project to study various factors on which the internal resistance emf of a cell depends
Two point charges q and -q are placed at a distance d apart.What are the points at which resultant electric field is parallel to the line joining the two charges?
A free proton and a free electron are placed in a uniform field. Which of the twoexperience greater force and greater acceleration?
State and prove Gauss Theorem.
What is the angle between the directions of electric field at any 1) axial point 2) equatorial point due to an electric dipole ?
a man in an insulated metallic cage does not receive a shock, even when the cage is connected to a high voltage source.why?
what are the physical significance of electric field??
A cup contains 250g of water. find number of positive charges present in the cup of water?
the sum of two point charges is 7uC. they repel each other with a force of 1N when kept 30cm apart in free space. calculate the value of each charge.
four particles form a square. the charges are q1 = q4 = Q & q2 = q3 = q
(a) What is Q/q if the net electostatic force on particles 1& 4 is zero? (b) is there any value of q that makes the net electrostatic force on each of the four particles zero? Explain.
If E=6i+3j+4k, calculate the electric flux through a surface of area 20 units in the YZ plane.
HOW TO DO THIS QUESTION?
The electric field components due to a charge inside the cube of side 0.1 m are as shown:
Where α = 500 N/C − m
Ey= 0,Ez= 0
Calculate (i) the flux through the cube and (ii) the charge inside the cube
why is coulombs law applicable only to point charges?
explain cyclotron in a more elaborate way
what is the source charge and test charge
A certain charge Q is divided into two parts q and Q-q which are then seperated by a certain distance.What must q be iin terms of Qto maximise the electrostatics repulsion between the two charges?
Why does the electric field inside a dielectric decrease when it is placed in an external electric field?
a car moving with a speed of 40km/hr can be stopped by applying brakes after at least 2m.If the same car is moving with 80km/hr.What is the least stopping distance?
a semi infinite line charge of linear charge density 'D' has the shape of an infinitely long straight wire whose one end is connected to three-fourth circle of radius 'R' while one of the diameters of 3/4th circle is parallel to the infinitely long straight part.What is the field at the centre of the circle.How?
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Syllabus
what is the meaning of quantisation of charge?
state any two postulates of bohr's theory of hydrogen atom. what is the maximum possible number of spectral lines observed when hydrogen atom is in its second excited state. justify your answer. calculate ratio of the maximum and minimum wavelength of the radiations emitted in this process.
left wire is 2 A and directed out of the plane of the page and the current in
the right wire is 3 A and directed into the plane of the page. In which
region(s) is/are there a point on the x-axis, at which the magnetic field is
equal to zero due to these currents carrying wires? Justify your Answer?
Difference between gravitational force and electrostatic force
passing through the cube normally will be
what is the dimensional formula of epsilon not?
Two similarly and equally charged identical metal spheres A and B repel each other with a force of 0.000002 N. A third identical sphere C is touched with A and then placed at the mid point between A nd B. What is the net electric force on C?
Two charges,one +5 microcoulomb and other of -5microcoulomb are placed 1mm apart .Calculate the dipole moment
( ans 5*10 to the power -9 Cm)
Three point charges of +2 microcoulomb,-3 microcoulomb and -3 microcoulomb are kept at the vertices A,B and C respectively of an equilateral triangle of side 20 cm.What should be the sign and magnitude of the charge to be placed at the mid point(M) of side BC so that the charge at A remains in equilibrium?
what is N=nNa
A charge q is placed at the center of the line joining two equal charges Q. Show that the system of three charges will be in equilibrium if q = -Q/4.
derive an expression for potential energy of an electric dipole in a uniform electric field .
An infinite number of charges each equal to q are placed along x axis at x=1 , x=2 , x=4, x=8 and so on . Find the electric field at the point where x=0 due to this setup of charges and what will be the electric field if inthe above setup the consecutive charges have opposite sign.?
Explain the formulae E = Sigma / Epsilon not.
E is the electric field vector.
Epsilon not is the specific inductive capacity or relative permittivity of vaccum.
Sigma = ? (doubt)
what does q1+q2 =0 signify in electrostatics?
difference between uniform and non-uniform electric fields.... plzz if possible draw diagrams too..!
a gas is heated through 1 degree celsius in a closed vessel. its pressure is increased by 0.4%.the initial temperature of the gas is ????
A stream of electrons travelling with speed of v m/s at right angles to a uniform electric field E is deflected in a circular path of radius r.Prove that e/m =v2 /rE ?
A charge "q" is placed at the centre of the cube of side "l". What is the electric flux passing through each face of the cube?
Pls provide chart for values of Sin, Cos, Tan and Cot for specific values from 30 degrees to 360 degrees.
 What is quantisation of charge?
What are the limitations of Coulomb's Law ?
if a point charge be rotated in a circle of radius r around a charge q ,what will be work done ?
A pendulum bob of mass of 80 mg and carrying a charge of 2 X 10-8 C is at rest in a horizontal uniform electric field of 20,000 V/m. Find the tension in the thread of the pendulum and the angle it makes with the vertical.
Take( g = 9.8ms-2 )
Determine the electric field at (a) a point P on the axis of the dipole 15 cm away from its centre O on the side of the positive charge, as shown in Fig. 1.21(a). and (b) a point Q, 15 cm away from O on a line
passing through O and normal to the axis of the dipole. as shown in Fig. 1.21(b).
Four charges, each equal to Q are placed at the 4 corners of a square and a charge q is placed at the centre of the square. If the system is in equilibrium, then the value of q is?
what is the least possible value of electric charge?
two equal point charges A and B are R distance apart. A third point charge placed on the prependicular bisector at a distance 'd' from the center will experience maximum electrostatic force when
1. d = R/2 X 1.414
2 d = R/ 1.414
3. d = R 1.414
4. d = 2 X 1.414 R
name the system for which electric field at distances 1cm,2cm,3cm are in the ratio 1:1/8:1/27
Three charges each equal to q are placed at the three corners of a square of side a. Find the electric field at the fourth corner.
Electric field strength, E=V/r what is V and r
when a body becmes negatively charged , its mass
[a] decreases [b] increases
[c] remins the same [d] none of these
q. Two point charges of +16 micro coulomb and -9 micro coulomb are placed 8 cm apart in air .Determine the position of the point at which the resultant field is zero .
Two small balls having equal positive charge q coulomb are suspended by two insulating strings of equal length ' l ' meter from hook fixed to stand.The whole setup is taken in a satellite into sapce where there is no gravity. What is the angle between the two strings and the tension in each string?
an electric dipole of dipole moment 20 *10-6Cm is enclosed by a closed surface .what is the net flux coming out of the surface?
Q. Moment of inertia of a semicircular ring of radius R and mass M; about an axis passing through A and perpendicular to the plane of the paper is
ans d
2 point charges at distance ' r ' in air exert a force ' F ' on each other, at what distance will these charges experience the same force ' F' in a medium of dielectric constant K?
two fixed point charges +4e and +e units are separated by a distance a .where should the third point charge be placed for it to be in equilibrium ?
how much positive and negative charge is there in a cup of water
Q.4. Gauss's law should be invalid, if
(a) there were magnetic monopoles
(b) the inverse square law were not exactly true
(c) the velocity of light were not a universal constant
(d) None of the above
Two infinitely long parallel wires having linear charge densities λ1 and λ2 respectively are placed at a distance of R metre. The force per unit length on either wire will be.......?
what is the direction of electric field at the surface of a charged conductor having charge density σ < 0.
what is the principle of vernier calipers
why do electrostatic experiments not work well on humid days
electrostatic field lines cannot be discontinuous why?
An electron falls through a distance of 1.5 cm in a uniform electric field of magnitude 2.0 × 104 N C–1 in the direction of the field . Then the direction of the field is reversed keeping its magnitude unchanged and a proton falls through the same distance . compute the time of fall in each case.
state Gauss' law in electrostatics.
Q.29. The three water filled tanks shown have the same volume and height. If small identical holes are punched near this bottom, which one will be the first to get empty?
A) (i)
B) (ii)
C) (iii)
D) All will take same time
project to study various factors on which the internal resistance emf of a cell depends
Two point charges q and -q are placed at a distance d apart.What are the points at which resultant electric field is parallel to the line joining the two charges?
Find (i) the force on the charge at the centre of shell and at the point A. (ii) the electric flux through the shell.
A free proton and a free electron are placed in a uniform field. Which of the two
experience greater force and greater acceleration?
State and prove Gauss Theorem.
What is the angle between the directions of electric field at any 1) axial point 2) equatorial point due to an electric dipole ?
a man in an insulated metallic cage does not receive a shock, even when the cage is connected to a high voltage source.why?
what are the physical significance of electric field??
A cup contains 250g of water. find number of positive charges present in the cup of water?
the sum of two point charges is 7uC. they repel each other with a force of 1N when kept 30cm apart in free space. calculate the value of each charge.
four particles form a square. the charges are q1 = q4 = Q & q2 = q3 = q
(a) What is Q/q if the net electostatic force on particles 1& 4 is zero? (b) is there any value of q that makes the net electrostatic force on each of the four particles zero? Explain.
If E=6i+3j+4k, calculate the electric flux through a surface of area 20 units in the YZ plane.
HOW TO DO THIS QUESTION?
The electric field components due to a charge inside the cube of side 0.1 m are as shown:
Ey= 0,Ez= 0
Calculate (i) the flux through the cube and (ii) the charge inside the cube
why is coulombs law applicable only to point charges?
explain cyclotron in a more elaborate way
what is the source charge and test charge
A certain charge Q is divided into two parts q and Q-q which are then seperated by a certain distance.What must q be iin terms of Qto maximise the electrostatics repulsion between the two charges?
Why does the electric field inside a dielectric decrease when it is placed in an external electric field?
(a) These originate from positive charge and end on negative charge
(b) they do not intersect each other at a point
(c) They have the same form for a point charge and a sphere.
(d) They have spherical existence.
a car moving with a speed of 40km/hr can be stopped by applying brakes after at least 2m.If the same car is moving with 80km/hr.What is the least stopping distance?
and q2
such that
(i) q1q2
> 0; q1
> q2
> 0 (ii) q1 q2
> |?q2
| | > |?q2
|
a semi infinite line charge of linear charge density 'D' has the shape of an infinitely long straight wire whose one end is connected to three-fourth circle of radius 'R' while one of the diameters of 3/4th circle is parallel to the infinitely long straight part.What is the field at the centre of the circle.How?
Q. Three point masses, M each, are moving in a circle, each with a speed v, under their mutual gravitational attractive force. The distance between any two masses must be :
(A) 2 GM/
B) 3 GM/
C) GM/
D) GM/