1
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
$${1 \over {\sqrt 3 }}{\tau \over {Bi}}$$
2
AIPMT 2005
MCQ (Single Correct Answer)
+4
-1
Zener diode is used for
A
amplification
B
rectification
C
stabilisation
D
producing oscillations in an oscillator.
3
AIPMT 2005
MCQ (Single Correct Answer)
+4
-1
Copper has face centered cubic (fcc) lattice with interatomic spacing equal to 2.54 $$\mathop A\limits^ \circ $$. The value of lattice constant for this lattice is
A
2.54 $$\mathop A\limits^ \circ $$
B
3.59 $$\mathop A\limits^ \circ $$
C
1.27 $$\mathop A\limits^ \circ $$
D
5.08 $$\mathop A\limits^ \circ $$
4
AIPMT 2005
MCQ (Single Correct Answer)
+4
-1
Carbon, silicon and germanium atoms have four valence electrons each. Their valence and conduction bands are separated by energy band gaps represented by (Eg)C, (Eg)si and (Eg)Ge respectively. Which one of the following relationships is true in their case?
A
(Eg)C > (Eg)Si
B
(Eg)C < (Eg)Si
C
(Eg)C = (Eg)Si
D
(Eg)C < (Eg)Ge.