1
AIPMT 2005
MCQ (Single Correct Answer)
+4
-1
Energy levels A, B and C of a certain atom corresponding to increasing values of energy i.e. EA < EB < EC. If $$\lambda $$1, $$\lambda $$2 and $$\lambda $$3 are wavelengths of radioations corresponding to transitions C to B, B to A and C to A respectively, which of the following relations is correct?
A
$${\lambda _3} = {\lambda _1} + {\lambda _2}$$
B
$${\lambda _3} = {{{\lambda _1}{\lambda _2}} \over {{\lambda _1} + {\lambda _2}}}$$
C
$${\lambda _1} + {\lambda _2} + {\lambda _3} = 0$$
D
$${\lambda _3}^2 = {\lambda _1}^2 + {\lambda _2}^2$$
2
AIPMT 2005
MCQ (Single Correct Answer)
+4
-1
In a p-n junction photo cell, the value of the photo-electromotive force profuced by monochromatic light is proportional to
A
The barrier voltage at the p-n junction.
B
The intensity of the light falling on the cell.
C
The frequency of the light falling on the cell.
D
The voltage applied at the p-n junction.
3
AIPMT 2005
MCQ (Single Correct Answer)
+4
-1
Fission of nuclei is possible because the binding energy per nucleon in them
A
increases with mass number at low mass numbers
B
decreases with mass number at low mass numbers
C
increases with mass number at high mass numbers
D
decreases with mass number at high mass numbers.
4
AIPMT 2005
MCQ (Single Correct Answer)
+4
-1
Choose the only false statement from the following.
A
In conductors the valence and conduction bands overlap.
B
Substances with energy gap of the order of 10 eV are insulators.
C
The resistivity of a semiconductor increases with increase in temperature.
D
The conductivity of a semiconductor increases with increase in temperature.