1
NEET 2017
MCQ (Single Correct Answer)
+4
-1
The de-Broglie wavelength of a neutron in thermal equilibrium with heavy water at a temperature T (kelvin) and mass m, is
A
$${h \over {\sqrt {3mkT} }}$$
B
$${{2h} \over {\sqrt 3 mkT}}$$
C
$${{2h} \over {\sqrt {mkT} }}$$
D
$${h \over {\sqrt {mkT} }}$$
2
NEET 2017
MCQ (More than One Correct Answer)
+4
-1
The photoelectric threshold wavelength of silver is 3250 $$ \times $$ 10$$-$$10 m. The velocity of the electron ejected from a silver surface by ultraviolet light of wavelength 2536 $$ \times $$ 10$$-$$10 m is
{Given h = 4.14 $$ \times $$ 10$$-$$15 eV s and c = 3 $$ \times $$ 108 m s$$-$$1 ]
A
$$ \approx $$ 0.6 $$ \times $$ 106 m s$$-$$1
B
$$ \approx $$ 61 $$ \times $$ 103 m s$$-$$1
C
$$ \approx $$ 0.3 $$ \times $$ 106 m s$$-$$1
D
$$ \approx $$ 6 $$ \times $$ 105 m s$$-$$1
3
NEET 2017
MCQ (Single Correct Answer)
+4
-1
Out of Syllabus
Radioactive material 'A' has decay constant '8 $$\lambda $$' and material 'B' has decay constant '$$\lambda $$'. Initially they have same number of nuclei. After what time, the ratio of number of nuclei of material 'B' to that 'A' will be e ?
A
$${1 \over {7\lambda }}$$
B
$${1 \over {8\lambda }}$$
C
$${1 \over {9\lambda }}$$
D
$${1 \over {\lambda }}$$
4
NEET 2017
MCQ (Single Correct Answer)
+4
-1
The ratio of wavelengths of the last line of Balmer series and the last line of Lyman series is
A
1
B
4
C
0.5
D
2
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Medical
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Graduate Aptitude Test in Engineering
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