Electric Charges and Fields — practice questions
65 curated practice questions from Electric Charges and Fields (Physics Class 12, CBSE) — 23 easy, 36 medium, 6 hard. Every question includes the final answer free; step-by-step worked solutions with a free account.
- If the net electric flux through a closed surface is zero, then we can infer
- Two charges q 1 and q 2 are placed at the centres of two spherical conducting shells of radius r 1 and r 2…
- The magnitude of electric field due to a point charge 2q, at distance r is E. Then the magnitude of electric field due…
- Suppose the charge of a proton and an electron differ slightly. One of them is -e, the other is (e + e). If the net of…
- Two parallel large thin metal sheets have equal surface charge densities of 2.56 10^ -11 C m ^ -2 of opposite signs…
- Two charged particles P and Q, having the same charge but different masses m _ P and m _ Q , start from rest and travel…
- The electric field required to keep a water drop of mass m just to remain suspended, when charged with one electron, is
- If = surface charge density, = electric permittivity, the dimensions of are same as
- Which one of the following is not a scalar quantity?
- Three small charged spheres X, Y and Z carrying charges + q, q and + q respectively are placed equidistant from each…
- The specific charge of a proton is 9.6 × 10 7 C kg –1 . The specific charge of an alpha particle will be
- A charge Q is placed at the centre of a cube. The electric flux through one if its face is
- A thin plastic rod is bent into a circular ring of radius R. It is uniformly charged with charge density . The…
- The electric field due to a uniformly charged sphere of radius R as a function of the distance from its centre is…
- An electric dipole consisting of charges + q and - q separated by a distance L is in stable equilibrium in a uniform…
- Two charged spheres separated at a distance d exert a force F on each other. If they are immersed in a liquid of…
- Two infinitely long parallel conducting plates having surface charge densities + and - respectively are separated by a…
- Two pith balls carrying equal charges are suspended from a common point by strings of equal length, the equilibrium…
- An electron is moving round the nucleus of a hydrogen atom in a circular orbit of radius r. The Coulomb force F between…
- A conducting sphere of radius R = 20 cm is given a charge Q = 16 C. What is E at its centre?
- An electric dipole of dipole moment 1.0 10^ -12 Cm lies along x-axis. An electric field of magnitude 2.0 10^ 4 NC ^ -1…
- A point charge Q is placed at the mid point of a line joining two charges, 4q and q. If the net force on charge q is…
- Two identical point charges are placed at the two vertices A and B of an equilateral triangle of side l . The magnitude…
- Two charged particles P and Q, having the same charge but different masses m _ P and m _ Q , start from rest and travel…
- Assertion (A): Acceleration of charged particles in the non-uniform electric field does not depend on the velocity of a…
- A charged sphere of radius r has surface charge density. The electric field on its surface is E. If the radius of the…
- The Coulomb force (F) versus ( 1 / r ^ 2 ) graphs for two pairs of point charges ( q _ 1 and q _ 2 ) and ( q _ 2 and q…
- When 10 19 electrons are removed from a neutral metal plate, the electric charge on it is
- A charge Q is enclosed by a Gaussian spherical surface of radius R. If the radius is doubled, then the outward electric…
- In air the value of the total electric flux emitted from the unit positive charge is
- What is the net charge on a conducting sphere of radius 10 cm? Given that the electric field 15 cm from the centre of…
- The unit of permittivity of free space ( _0 ) is
- Two point charges Q and -q are held 'r' disapart in free space. A uniform electric field E is applied in the region…
- An electric dipole of moment p is placed in an electric field of intensity E. The dipole acquires a position such that…
- Two large conducting spheres carrying charges Q 1 and Q 2 are kept with their centres r distance apart. The magnitude…
- Two identical small conducting balls B _ 1 and B _ 2 are given -7 pC and +4 pC charges respectively. They are brought…
- Out of the following which one is not a property of field lines:
- Assertion (A): If the bob of a simple pendulum is kept in a horizontal electric field, its period of oscillation will…
- A point charge q is kept at a distance r from an infinitely long straight wire with charge density . The magnitude of…
- The electric field due to an infinitely long, straight, uniformly and positively charged wire at a point at distance r…
- The electric flux through a closed Gaussian surface depends upon
- Figure shows variation of Coulomb force (F) acting between two point charges with 1 r^ 2 , r being the separation…
- A point P lies on the perpendicular bisect of an electric dipole of dipole moment p. If the distance of P from the…
- Which one of the following statements is correct? Electric field due to static charges is
- Four objects W, X, Y and Z, each with charge +q are held fixed at four points of a square of side d as shown in the…
- A charge q is located at the centre of a cube. The electric flux through any face is
- Four charges are arranged at the corners of a square as shown in the figure. The direction of electric field at the…
- A charge Q is fixed in position. Another charge q is brought near charge Q and released from rest. Which of the…
- An infinitely long uniformly charged wire produces an electric field of 18 10 4 NC -1 at a distance of 1.0 cm. The…
- Three charged particles are collinear and are in equilibrium, then
- An early model for an atom considered it to have a positively charged point nucleus of charge Ze, surrounded by a…
- When air is replaced by a dielectric medium of dielectric constant , the maximum force of attraction between two…
- A charge q C is placed at the centre of a cube of side 0.1 m. Then the electric flux diverging from each face of this…
- Two identical charged spheres suspended from a common point by two massless strings of lengths l, are initially at a…
- An electron of mass m e , initially at rest, moves through a certain distance in a uniform electric field in time t 1 …
- A uniformly charged non-conducting disc with surface charge density 10 nC/m 2 has radius R = 3 cm. The magnitude of the…
- A charged cloud system produces an electric field in the air near the earth's surface. A particle of charge -2 10 -9 C…
- Consider two identical dipoles D _ 1 and D _ 2 . Charges -q and q of dipole D _ 1 are located at (0,0) and ( a , 0) and…
- For coulomb force to be operative the least size of the atom will be
- An electron experiences a force (1.6 10^ -16 ~N ) i in an electric field E . The electric field E is:
- The electric field (E) and electric potential (V) at a point inside a charged hollow metallic sphere are respectively:
- An electric dipole placed in non-uniform electric field experiences:
- A small metallic sphere S of charge +q is placed exactly at a point midway between two-point charges A (+ Q ) and B (+…
- A particle of mass m and charge -q is moving with a uniform speed v in a circle of radius r, with another charge q at…
- A charged particle of mass m and charge q initially at rest is released in an electric field of magnitude E. Its…