According to the Bohr theory, which of the following transitions in the hydrogen atom will give rise to the least energetic photon ?
A
n = 6 to n = 1
B
n = 5 to n = 4
C
n = 6 to n = 5
D
n = 5 to n = 3
2
AIPMT 2011 Mains
MCQ (Single Correct Answer)
+4
-1
A thermocouple of negligible resistance
produces an e.m.f. of 40 µV/ºC in the linear range
of temperature. A galvanometer of resistance 10
ohm whose sensitivity is 1 µA/division, is
employed with the thermocouple. The smallest
value of temperature difference that can be
detected by the system will be
A
1ºC
B
0.5 ºC
C
0.1ºC
D
0.25ºC
3
AIPMT 2011 Mains
MCQ (Single Correct Answer)
+4
-1
A galvanometer of resistance, G, is shunted by a resistance S ohm. To keep the main current in the circuit unchanged, the resistance to be put in series with the galvanometer is
A
$${G \over {(S + G)}}$$
B
$${{{S^2}} \over {\left( {S + G} \right)}}$$
C
$$\left( {{{SG} \over {S + G}}} \right)$$
D
$${{{G^2}} \over {(S + G)}}$$
4
AIPMT 2011 Mains
MCQ (Single Correct Answer)
+4
-1
A Zener diode, having breakdown voltage equal to 15 V, is used in a voltage regulator circuit shown in figure. The current through the diode is
