1
WB JEE 2017
MCQ (Single Correct Answer)
+1
-0.25
Change Language
WB JEE 2017 Physics - Geometrical Optics Question 17 English
A parallel beam of light is incident on a glass prism in the shape of a quarter cylinder of radius R = 0.05 m and refractive index n = 1.5, placed on a horizontal table as shown in the figure. Beyond the cylinder, a patch of light is found whose the nearest distance x from the cylinder is
A
$$(3\sqrt 3 - 4) \times {10^{ - 2}}$$ m
B
$$(2\sqrt 3 - 2) \times {10^{ - 2}}$$ m
C
$$(3\sqrt 5 - 5) \times {10^{ - 2}}$$ m
D
$$(3\sqrt 2 - 3) \times {10^{ - 2}}$$ m
2
WB JEE 2017
MCQ (Single Correct Answer)
+1
-0.25
Change Language
The de-Broglie wavelength of an electron is $$0.4 \times {10^{ - 10}}$$ m when its kinetic energy is 1.0 keV. Its wavelength will be $$1.0 \times {10^{ - 10}}$$ m, when its kinetic energy is
A
0.2 keV
B
0.8 keV
C
0.63 keV
D
0.16 keV
3
WB JEE 2017
MCQ (Single Correct Answer)
+1
-0.25
Change Language
When light of frequency v1 is incident on a metal with work function W (where hv1 > W), then photocurrent falls to zero at a stopping potential of V1. If the frequency of light is increased to v2, the stopping potential changes to V2. Therefore, the charge of an electron is given by
A
$${{W({v_2} + {v_1})} \over {{v_1}{V_2} + {v_2}{V_1}}}$$
B
$${{W({v_2} + {v_1})} \over {{v_1}{V_1} + {v_2}{V_2}}}$$
C
$${{W({v_2} - {v_1})} \over {{v_1}{V_2} - {v_2}{V_1}}}$$
D
$${{W({v_2} - {v_1})} \over {{v_2}{V_2} - {v_1}{V_1}}}$$
4
WB JEE 2017
MCQ (Single Correct Answer)
+1
-0.25
Change Language
Radon-222 has a half-life of 3.8 days. If one starts with 0.064 kg of radon-222 left after 19 days will be
A
0.002 kg
B
0.062 kg
C
0.032 kg
D
0.024 kg
EXAM MAP
Medical
NEETAIIMS
Graduate Aptitude Test in Engineering
GATE CSEGATE ECEGATE EEGATE MEGATE CEGATE PIGATE IN
Civil Services
UPSC Civil Service
Defence
NDA
Staff Selection Commission
SSC CGL Tier I
CBSE
Class 12