1
NEET 2016 Phase 2
MCQ (Single Correct Answer)
+4
-1
Change Language
An air bubble in a glass slab with refractive index 1.5 (near normal incidence) is 5 cm deep when viewed from one surface and 3 cm deep when viewed from the opposite face. The thickness (in cm) of the slab is
A
8
B
10
C
12
D
16
2
NEET 2016 Phase 2
MCQ (Single Correct Answer)
+4
-1
Change Language
Photons with energy 5 eV are incifent on a cathode C in a photoelectric cell. The maximum energy of emitted photoelectrons is 2 eV. When photons of energy 6 eV are incident on C, no photoelectrons will reach the anode A, if the stopping potential of A relative to C is
A
+ 3 V
B
+4 V
C
$$-$$1 V
D
$$-$$3 V
3
NEET 2016 Phase 2
MCQ (Single Correct Answer)
+4
-1
Change Language
Electrons of mass m with de-Broglie wavelength $$\lambda $$ fall on the target in an X-ray tube. The cutoff wavelength ($$\lambda $$0) of the emitted X-ray is
A
$$\lambda $$0 = $${{2mc{\lambda ^2}} \over h}$$
B
$${\lambda _0} = {{2h} \over {mc}}$$
C
$${\lambda _0} = {{2{m^2}{c^2}{\lambda ^3}} \over {{h^2}}}$$
D
$${\lambda _0} = \lambda $$
4
NEET 2016 Phase 2
MCQ (Single Correct Answer)
+4
-1
Change Language
If an electron in a hydrogen atom jumps from the 3rd orbit to the 2nd orbit, it emits a photon of wavelength $$\lambda $$. When it jumps from the 4th orbit to the 3rd orbit, the corresponding wavelength of the photon will be
A
$${{16} \over {25}}\lambda $$
B
$${9 \over {16}}\lambda $$
C
$${{20} \over 7}\lambda $$
D
$${{20} \over {13}}\lambda $$