Advertisements
Advertisements
Question
A man stands 10 m in front of a large plane mirror. How far must the walk before he is 5 m away from his image?
Advertisements
Solution
Man should walk 7.5 m towards the mirror.
The reason being, the image formed by a plane mirror is the same distance behind the mirror as it is between the object and the mirror. A distance of 5m between man and his image means that the distance between him and the mirror = `52`= 2.5 m.
Thus, the distance he should walk = 10 - 2.5 = 7.5 m.
APPEARS IN
RELATED QUESTIONS
Name the phenomenon responsible for the following effect:
When we sit in front of a plane mirror and write with our right hand, if appears in the mirror that we are writing with the left hand.
If an object is placed at a distance of 10 cm in from of a plane mirror, how far would it be from its image?
Write the word AMBULANCE as it would appear when reflected in a plane mirror. Why is it sometimes written in this way (as its mirror image) on the front of an ambulance?
A wall reflects light and a mirror also reflects light. What difference is three in the way they reflect light?
Explain why, though both a plane mirror and a sheet of paper reflect light but we can see the image of our face in a plane mirror but not in a sheet of paper.
A ray of light goes from water into air. Will it bend towards the normal or away from the normal?
In which material do you think light rays travel faster-glass or air?
With the help of a diagram, show how when light falls obliquely on the side of a rectangular glass slab, the emergent ray is parallel to the incident ray.
The speed of light is more in glass than in water.
The depth of a pond when seen from above appears to be less.
Image is formed by a mirror due to refraction of light.
Choose and write the correct option.
If we gradually increase the angle of incidence of a ray of light passing through prism then …..
Explain how the formation of a rainbow occurs.
Lights of different colours are used as signal for safety transport. From these, the wavelength of red light is _______ nm.
Write scientific reason.
The coin disappears in a vessel as it is seen from a specific location. But as soon as the water is poured into the vessel to a certain level, the coin appears.
State whether true or false. If false, correct the statement.
The angle of deviation depends on the refractive index of the glass.
You are given water, mustard oil, glycerine and kerosene. In which of these media a ray of light incident obliquely at same angle would bend the most?

In the above diagram light is travelling through different media. It is noted by a scientist that ∠1= ∠3 = ∠4 but ∠2 < ∠1. Which of the following statement would be correct?
The bottom of swimming pool appears to be less deep than the actual one because of
