Q1: Four students A, B, C, D perform experiment on tracing the path of light ray through a glass slab. The position of the pins used to describe incident ray is shown on paper by four of them, respectively as:
The correct result will be obtained by :
(a) A and D both
(b) B and D both
(c) B only
(d) B and C both
Answer: (d) B and C both
Q2: Teacher asked three students to write one precaution by each of them regarding the experiment on tracing the path of light ray through glass slab. First, second and third student wrote down following precautions, respectively
(1) While tracing emergent ray, we should see heads of pins.
(2) One eye should be kept closed, while tracing emergent ray
(3) Glass slab should have parallel edges.
The correct statements are of:
(a) 1 and 2
(b) 2 and 3
(c) 1 and 3
(d) All three
Answer: (b) 2 and 3 (Note: We should see the feet of the pins.)