1
AIPMT 2010 Prelims
+4
-1
Two positives ions, each carrying a charge q, are separated by a distance d. If F is the force of repulsion between the ions, the number of electrons missing from each ion will be (e being the charge on an electron)
A
$${{4\pi {\varepsilon _0}F{d^2}} \over {{e^2}}}$$
B
$$\sqrt {{{4\pi {\varepsilon _0}F{e^2}} \over {{d^2}}}}$$
C
$$\sqrt {{{4\pi {\varepsilon _0}F{d^2}} \over {{e^2}}}}$$
D
$${{4\pi {\varepsilon _0}F{d^2}} \over {{q^2}}}$$
2
AIPMT 2010 Prelims
+4
-1
A square surface of side L meter in the plane of the paper is placed in a uniform electric field $$E$$(volt/m) acting along the same plane at an angle $$\theta$$ with the horizontal side of the square as shown in figurre.

The electric flux linked to the surface, in units of volt m is
A
EL2
B
EL2cos$$\theta$$
C
EL2sin$$\theta$$
D
zero
3
AIPMT 2009
+4
-1
Three concentric spherical shells have radii a, b and c (a < b < c) anf have surface charge densities $$\sigma$$, $$-$$$$\sigma$$ and $$\sigma$$ respectively. If VA, VB and VC denote the potentials of the three shells, then, for c = a + b, we have
A
VC = VB $$\ne$$ VA
B
VC $$\ne$$ VB $$\ne$$ VA
C
VC = VB = VA
D
VC = VA $$\ne$$ VB
4
AIPMT 2009
+4
-1
The electric potential at a point (x, y, z) is given by V = $$-$$x2y $$-$$ xz3 + 4

The electric field at that point is
A
$$\overrightarrow E = \widehat i2xy + \widehat j\left( {{x^2} + {y^2}} \right) + \widehat k\left( {3xz - {y^2}} \right)$$
B
$$\overrightarrow E = \widehat i{z^3} + \widehat jxyz + \widehat k{z^2}$$
C
$$\overrightarrow E = \widehat i\left( {2xy - {z^3}} \right) + \widehat jx{y^2} + \widehat k3{z^2}x$$
D
$$\overrightarrow E = \widehat i\left( {2xy + {z^3}} \right) + \widehat j{x^2} + \widehat k3x{z^2}$$
EXAM MAP
Medical
NEET