1
AIPMT 2005
MCQ (Single Correct Answer)
+4
-1
As per the diagram a point charge +q is placed at the origin O. Work done in taking another point charge $$-$$Q from the point A [coordinates (0, $$a$$)] to another point B

AIPMT 2005 Physics - Electrostatics Question 40 English
A
zero
B
$$\left( {{{qQ} \over {4\pi {\varepsilon _0}}}{1 \over {{a^2}}}} \right).\sqrt 2 a$$
C
$$\left( {{{ - qQ} \over {4\pi {\varepsilon _0}}}{1 \over {{a^2}}}} \right).\sqrt 2 a$$
D
$$\left( {{{qQ} \over {4\pi {\varepsilon _0}}}{1 \over {{a^2}}}} \right).{a \over {\sqrt 2 }}$$
2
AIPMT 2005
MCQ (Single Correct Answer)
+4
-1
When a wire of uniform cross-section $$a$$ length $$l$$ and resistance R is bent into a complete circle. resistance between any two of diametrically opposite points will be
A
R/4
B
4R
C
R/8
D
R/2
3
AIPMT 2005
MCQ (Single Correct Answer)
+4
-1
A very long straight wire carries a current $$I$$. At the instant when a charge +Q at point P has velocity $$\overrightarrow v $$, as shown, the force on the charge is

AIPMT 2005 Physics - Moving Charges and Magnetism Question 38 English
A
along Oy
B
opposite to Oy
C
along Ox
D
opposite to Ox
4
AIPMT 2005
MCQ (Single Correct Answer)
+4
-1
A coil in the shape of an equilateral triangle of side $$l$$ is suspended between the pole pieces of a permanent magnet such that $$\overrightarrow B $$ is in plane of the coil. If due to a current i in the triangle a torque $$\tau $$ acts on it, the side $$l$$ of the triangle is
A
$${2 \over {\sqrt 3 }}\left( {{\tau \over {Bi}}} \right)$$
B
$$2{\left( {{\tau \over {\sqrt 3 Bi}}} \right)^{1/2}}$$
C
$${2 \over {\sqrt 3 }}{\left( {{\tau \over {Bi}}} \right)^{1/2}}$$
D
$${1 \over {\sqrt 3 }}{\tau \over {Bi}}$$