1
WB JEE 2020
MCQ (Single Correct Answer)
+1
-0.25
Change Language
An object, is placed 60 cm in front of a convex mirror of focal length 30 cm. A plane mirror is now placed facing the object in between the object and the convex mirror such that it covers lower half of the convex mirror. What should be the distance of the plane mirror from the object, so that there will be no parallax between the images formed by the two mirrors?
A
40 cm
B
30 cm
C
20 cm
D
15 cm
2
WB JEE 2020
MCQ (Single Correct Answer)
+1
-0.25
Change Language
A thin convex lens is placed just above an empty vessel of depth 80 cm. The image of a coin kept at the bottom of the vessel is thus formed 20 cm above the lens. If now water is poured in the vessel upto a height of 64 cm, what will be the approximate new position of the image? Assume that refractive index of water is 4/3.
A
21.33 cm, above the lens
B
6.67 cm, below the lens
C
33.67 cm, above the lens
D
24 cm, above the lens
3
WB JEE 2020
MCQ (Single Correct Answer)
+2
-0.5
Change Language
A conducting circular loop of resistance 20$$\Omega $$ and cross-sectional area 20 $$ \times $$ 10-2 m2 is placed perpendicular to a spatially uniform magnetic field B, which varies with time t as B = 2sin(50$$\pi $$t) T. Find the net charge flowing through the loop in 20 ms starting from t = 0.
A
0.5 C
B
0.2 C
C
0 C
D
0.14 C
4
WB JEE 2020
MCQ (Single Correct Answer)
+2
-0.5
Change Language
A pair of parallel metal plates are kept with a separation d. One plate is at a potential + V and the other is at ground potential. A narrow beam of electrons enters the space between the plates with a velocity v0 and in a direction parallel to the plates. What will be the angle of the beam with the plates after it travels an axial distance L?
A
$${\tan ^{ - 1}}\left( {{{eVL} \over {md{v_0}}}} \right)$$
B
$${\tan ^{ - 1}}\left( {{{eVL} \over {mdv_0^2}}} \right)$$
C
$${\sin ^{ - 1}}\left( {{{eVL} \over {md{v_0}}}} \right)$$
D
$${\cos ^{ - 1}}\left( {{{eVL} \over {mdv_0^2}}} \right)$$
EXAM MAP
Medical
NEET
Graduate Aptitude Test in Engineering
GATE CSEGATE ECEGATE EEGATE MEGATE CEGATE PIGATE IN
Civil Services
UPSC Civil Service
Defence
NDA
CBSE
Class 12