Two pith balls carrying equal charges are suspended from a common point by strings of equal length, the equilibrium separation between them is r. Now the strings are rigidly clamped at half the height. The equilibrium separation between the balls now become
A
$$\left( {{{2r} \over {\sqrt 3 }}} \right)$$
B
$$\left( {{{2r} \over 3}} \right)$$
C
$${\left( {{1 \over {\sqrt 2 }}} \right)^2}$$
D
$$\left( {{r \over {\root 3 \of 2 }}} \right)$$
2
NEET 2013
MCQ (Single Correct Answer)
+4
-1
A, B and C are three points in a uniform electric field. The electric potential is
A
maximum at C
B
same at all the three points A, B and C
C
maximum at A
D
maximum at B
3
AIPMT 2012 Mains
MCQ (Single Correct Answer)
+4
-1
Two metallic spheres of radii 1 cm and 3 cm are given charges of $$-$$1 $$ \times $$ 10$$-$$2 C and 5 $$ \times $$ 10$$-$$2 C, respectively. If these are connected by a conducting wire, the final charge on the bigger sphere is
A
2 $$ \times $$ 10$$-$$2 C
B
3 $$ \times $$ 10$$-$$2 C
C
4 $$ \times $$ 10$$-$$2 C
D
1 $$ \times $$ 10$$-$$2 C
4
AIPMT 2012 Prelims
MCQ (Single Correct Answer)
+4
-1
An electric dipole of moment p is placed in an electric field of intensity E. The dipole acquires a position such that the axis of the dipole makes an angle $$\theta $$ with the direction of the field. Assuming that the potential energy of the dipole to be zero when $$\theta $$ = 90o, the torque and the potential energy of the dipole will respectively be