1
NEET 2023
+4
-1

In the figure shown here, what is the equivalent focal length of the combination of lenses (Assume that all layers are thin) ?

A
$$-40 \mathrm{~cm}$$
B
$$-100 \mathrm{~cm}$$
C
$$-50 \mathrm{~cm}$$
D
$$40 \mathrm{~cm}$$
2
NEET 2023
+4
-1

Two thin lenses are of same focal lengths $$(f)$$, but one is convex and the other one is concave. When they are placed in contact with each other, the equivalent focal length of the combination will be :

A
$$f / 4$$
B
$$f / 2$$
C
Infinite
D
Zero
3
NEET 2022 Phase 2
+4
-1

During a cloudy day, a primary and a secondary rainbow may be created, then the :

A
secondary rainbow is due to single internal reflection and is formed above the primary one.
B
primary rainbow is due to double internal reflection and is formed above the secondary one.
C
primary rainbow is due to double internal reflection and is formed below the secondary one.
D
secondary rainbow is due to double internal reflection and is formed above the primary one.
4
NEET 2022 Phase 2
+4
-1

An astronomical refracting telescope is being used by an observer to observe planets in normal adjustment. The focal lengths of the objective and eye piece used in the construction of the telescope are 20 m and 2 cm respectively. Consider the following statements about the telescope :

(a) The distance between the objective and eye piece is 20.02 m

(b) The magnification of the telescope is ($$-$$) 1000

(c) The image of the planet is erect and diminished

(d) The aperture of eye piece is smaller than that of objective

The correct statements are :

A
(a), (b) and (d)
B
(a), (b) and (c)
C
(b), (c) and (d)
D
(c), (d) and (a)
EXAM MAP
Medical
NEET