The law of reflection states that when a ray of light reflects off a surface, the
angle of incidence is equal to the angle of reflection.
Ramesh places
a mirror on level
ground to
determine the height of a pole (with traffic light fired on it). He stands at a
certain distance so that he can see the top of the pole reflected from the mirror.
Ramesh’s eye level is 1.5 m above the ground. The distance of Ramesh and the
pole from the mirror are 1.8 m and 6 m respectively.
On the basis of the above information, answer any four of the following
questions:
(i) Which criterion of similarity is applicable to similar triangles?
(a) SSA
(b) ASA
(c) SSS
(d) AA
(ii) What is the height of the pole?
(a) 6 metres
(b) 8 metres
(c) 5 metres
(d) 4 metres
(iii) If angle of incidence is i , which of the following is correct relation?
(a) tan i=5/6
(b) tan i= 6/5
(c) tan i= 3/5
(d) tan i= 5/3
(iv) Now Ramesh move behind such that distance between pole and Ramesh is
13 meters. He places mirror between him and pole to see the reflection of light
in right position. What is the distance between mirror and Ramesh ?
(a) 7 metres
(b) 3 metres
(c) 5 metres
(d) 4 metres
(v) What is the distance between mirror and pole?
(a) 9 metres
(b) 8 metres
(c) 12 metres
(d) 10 metre
Answers
Answer:
(i) Which criterion of similarity is applicable to similar triangles?
(d) AA
(ii) What is the height of the pole?
(c) 5 metres
(iii) If angle of incidence is i , which of the following is correct relation?
(a) tan i=5/6
Given : Ramesh’s eye level is 1.5 m above the ground. The distance of Ramesh and the pole from the mirror are 1.8 m and 6 m respectively.
To Find : (i) Which criterion of similarity is applicable to similar triangles?
(a) SSA
(b) ASA
(c) SSS
(d) AA
(ii) What is the height of the pole?
(a) 6 metres
(b) 8 metres
(c) 5 metres
(d) 4 metres
(iii) If angle of incidence is i , which of the following is correct relation?
(a) tan i=5/6
(b) tan i= 6/5
(c) tan i= 3/5
(d) tan i= 5/3
Solution:
criterion of similarity is applicable to similar triangles AA
as common angle and right angles are common
height of the pole = h
=> h/1.5 = 6/1.8
=> h = 9/1.8
=> h = 5 m
height of the pole = 5 m
Tan i = 5/6
Learn More:
The angle of elevation of top of a minor and angle of depression of ...
brainly.in/question/13899214
There is a small island in a river 18 m wide, and there is a treeon the ...
brainly.in/question/32213449