Ratio of longest wave lengths corresponding to Lyman and Balmer series in hydrogen spectrum is
A
$${7 \over {29}}$$
B
$${9 \over {31}}$$
C
$${5 \over {27}}$$
D
$${3 \over {23}}$$
2
NEET 2013
MCQ (Single Correct Answer)
+4
-1
A certain mass of Hydrogen is changed to Helium by the process of fusion. The mass defect in fusion reaction is 0.02866 u. The energy liberated per u is (given 1 u = 931 MeV)
A
6.675 MeV
B
13.35 MeV
C
2.67 MeV
D
26.7 MeV
3
NEET 2013
MCQ (Single Correct Answer)
+4
-1
The output (X) of the logic circuit shown ion figure will be
A
X = A . B
B
X = $$\overline {A + B} $$
C
X = $$\overline {\overline A } .\overline {\overline B } $$
D
X = $$\overline {A.B} $$
4
NEET 2013
MCQ (Single Correct Answer)
+4
-1
A piece of iron is heated in a flame. It first becomes dull red then becomes reddish yellow and finally turns to white hot. The correct explanation for the above observation is possible by using