An electron in hydrogen atom makes a transition n1 $$ \to $$ n2 where n1 and n2 are principal quantum numbers of the two states . Assuming Bohr's model to be valid, the time period of the electron in the initial state is eight times that in the final state. The possible values of n1 and n2 are
A
n1 = 6 and n2 = 2
B
n1 = 8 and n2 = 1
C
n1 = 8 and n2 = 2
D
n1 = 4 and n2 = 2
2
NEET 2013 (Karnataka)
MCQ (Single Correct Answer)
+4
-1
The output from a NAND gate is divided into two in parallel and fed to another NAND gate. The resulting gate is a
A
AND gate
B
NOR gate
C
OR gate
D
NOT gate
3
NEET 2013 (Karnataka)
MCQ (Single Correct Answer)
+4
-1
In an unbiased p-n junction, holes diffuse from the p-region to n-region because of
A
The attraction of free electrons of n-region.
B
The higher hole concentration in p-region than that in n-region.
C
The higher concentration of electrons in the n-region than that in the p-region.
D
The potential difference across the p-n junction.
4
NEET 2013 (Karnataka)
MCQ (Single Correct Answer)
+4
-1
One way in which the operation of a n-p-n transistor differs from that of a p-n-p
A
The emitter junction injects minority carries into the base region of the p-n-p
B
The emitter injects holes into the base of the p-n-p and electrons into the base region of n-p-n
