1
JEE Main 2021 (Online) 26th February Evening Shift
+4
-1
The incident ray, reflected ray and the outward drawn normal are denoted by the unit vectors $$\overrightarrow a$$, $$\overrightarrow b$$ and $$\overrightarrow c$$ respectively. Then choose the correct relation for these vectors.
A
$$\overrightarrow b$$ = $$\overrightarrow a$$ + 2$$\overrightarrow c$$
B
$$\overrightarrow b$$ = $$\overrightarrow a$$ $$-$$ 2 ($$\overrightarrow a$$ . $$\overrightarrow c$$)$$\overrightarrow c$$
C
$$\overrightarrow b$$ = 2$$\overrightarrow a$$ + $$\overrightarrow c$$
D
$$\overrightarrow b$$ = $$\overrightarrow a$$ $$-$$ $$\overrightarrow c$$
2
JEE Main 2021 (Online) 26th February Evening Shift
+4
-1
Given below are two statements : one is labeled as Assertion A and the other is labeled as Reason R.

Assertion A : For a simple microscope, the angular size of the object equals the angular size of the image.

Reason R : Magnification is achieved as the small object can be kept much closer to the eye than 25 cm and hence it subtends a large angle.

In the light of the above statements, choose the most appropriate answer from the options given below :
A
A is true but R is false
B
A is false but R is true
C
Both A and R are true and R is the correct explanation of A
D
Both A and R are true but R is NOT the correct explanation of A
3
JEE Main 2021 (Online) 26th February Morning Shift
+4
-1
A short straight object of height 100 cm lies before the central axis of a spherical mirror whose focal length has absolute value | f | = 40 cm. The image of object produced by the mirror is of height 25 cm and has the same orientation of the object. One may conclude from the information :
A
Image is real, same side of convex mirror.
B
Image is virtual, opposite side of convex mirror.
C
Image is virtual, opposite side of concave mirror.
D
Image is real, same side of concave mirror.
4
JEE Main 2021 (Online) 24th February Morning Shift
+4
-1
The focal length f is related to the radius of curvature r of the spherical convex mirror by :
A
f = r
B
f = $$-$$ r
C
f = +$${{1 \over 2}}$$ r
D
f = $$-$$$${{1 \over 2}}$$ r
EXAM MAP
Medical
NEET