CBSE
Multiple Choice QuestionsTwo spheres of same metal have radii a and b. Thet have been connected to a conducting wire. Find the ratio of the electric field intensity upon them.
a/b
b/a
b2 / a
b2/a2
A small piece of metal wire is dragged across the gap between the pole pieces of a magnet in 0.4 sec. If magnetic flux between the pole pieces is known to be 8 × 10-4 Wb, then induced emf in the wire, is
4 × 10-3 V
8 × 10-3 V
20 × 10-3 V
6 × 10-3 V
If Ea be the electric field strength of a short dipole at a point on its axial line and Ee that on equilateral line at the same distance, then
Ee = 2Ea
Ea = 2Ee
Ea = Ee
none of these
Length cannot be measure by
fermi
micron
debye
light year
The specific charge of a proton is 9.6 x107 C kg-1 The specific charge of an alpha particle will be
9.6 x107 C kg-1
19.2 x107 C kg-1
4.8 x107 C kg-1
2.4 x107 C kg-1
A Gaussian sphere encloses an electric dipole within it. The total flux across the sphere is
zero
half that due to a single charge
double that due to a single charge
dependent on the position of the dipole
Charges 4Q, q and Q are placed along x-axis at positions x = 0, x = l/2 and x = l, respectively. Find the value of q so that the force on charge Q is zero:
Q
-Q
Figure shows the electric lines of forces emerging from a charged body. If the electric field at A and B are EA and EB respectively and if the displacement between A and B is r, then
EA > EB
EA < EB
EA = EB/r
EA = EB / r2
Point charges + 4q, - q and+ 4q are kept on the x-axis at points x = 0, x = a and x = 2a respectively, then
only- q is in stable equilibrium
all the charges are in stable equilibrium
all the charges are in unstable equilibrium
none of the above
