Shown below is a distribution of charges. The flux of electric field due to these charges through the surface S is
(1)
(2)
(3)
(4) Zero
The electric flux for Gaussian surface A that enclose the charged particles in free space is (given q1 = –14 nC, q2 = 78.85 nC, q3 = – 56 nC)
(1) 103 Nm2 C–1
(2) 103 CN-1 m–2
(3) 6.32 × 103 Nm2 C–1
(4) 6.32 × 103 CN-1 m–2
The electric intensity due to an infinite cylinder of radius R and having charge q per unit length at a distance r(r > R) from its axis is
(1) Directly proportional to r2
(2) Directly proportional to r3
(3) Inversely proportional to r
(4) Inversely proportional to r2
A positively charged ball hangs from a silk thread. We put a positive test charge q0 at a point and measure F/q0, then it can be predicted that the electric field strength E
(1) > F/q0
(2) = F/q0
(3) < F/q0
(4) Cannot be estimated
The charge on 500 cc of water due to protons will be:
1. | 6.0 × 1027 C | 2. | 2.67 × 107 C |
3. | 6 × 1023 C | 4. | 1.67 × 1023 C |
An electric dipole is situated in an electric field of uniform intensity E whose dipole moment is p and moment of inertia is I. If the dipole is displaced slightly from the equilibrium position, then the angular frequency of its oscillations is
(1)
(2)
(3)
(4)
Two-point charges, +q and –q are held fixed at (–d, 0) and (d, 0) respectively of an (x, y) coordinate system. Then:
1. | E at all points on the y-axis is along . |
2. | The electric field at all points on the x-axis has the same direction. |
3. | Dipole moment is 2qd directed along . |
4. | Work has to be done in bringing a test charge from infinity to the origin. |
The electric field due to a uniformly charged sphere of radius R as a function of the distance from its centre is represented graphically by
(1) (2)
(3) (4)
Suppose the charge of a proton and an electron differ slightly. One of them is -e and the other is . If the net of electrostatic force and gravitaional force between two hydrogen atoms placed at a distance d (much greater than atomic size) apart is zero,then is of the order [Given mass of hydrogen, =1.67 kg]
(a)
(b)
(c)
(d)
An electric dipole is place at an angle of with an electric field intensity 2 N/C. It experiences a torque equal to 4 Nm. The charge on the dipole, if the dipole length is 2 cm, is
(a) 8 mC (b) 2 mC
(c) 5 mC (d) 7 C