Advertisements
Advertisements
Question
Lights of different colours are used as signal for safety transport. From these, the wavelength of red light is _______ nm.
Options
400
500
600
700
Advertisements
Solution
Lights of different colours are used as signal for safety transport. From these, the wavelength of red light is 700 nm.
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.
Which property of light makes a pencil cast a shadow when it is held in front of a light source?
State whether the following statement is true of false:
A student says that we can see an object because light from our eyes is reflected back by the object.
Where is the image when you look at something in a mirror?
A ray of light strikes a plane mirror such that its angle of incidence is 30°. What angle does the reflected ray make with the mirror surface?
An extended object in the form of an arrow pointing upward has been placed in front of a plane mirror. Draw a labelled ray-diagram to show the formation of its image.
What is meant by 'reflection of light'?
With the help of a labelled ray-diagram, describe how a plane mirror forms an image of a point source of light placed in front of it. State the characteristics of the image formed in a plane mirror.
The image in a plane mirror is virtual and laterally inverted. What does this statement mean?
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?
Explain how to read the following message which was found on some blotting paper:
State whether the following statement is true or false:
Refraction occurs because light slows down in denser materials.
Fill in the following blank with suitable word:
Light travelling along a normal is ...............refracted.
Fill in the following blank with suitable word:
Light bends when is passes from water into air. We say that it is ............
When a light ray passes from air into glass, what happens to its speed? Draw a diagram to show which way the ray of light bends.
With the help of a labelled diagram, explain why a tank full of water appears less deep than it actually is.
Show the lateral displacement of the ray on the diagram.
State two factors on which the lateral displacement of the emergent ray depends.
When a ray of light travelling in glass enters into water obliquely:
(a) it is refracted towards the normal
(b) it is not refracted at all
(c) it goes along the normal
(d) it is refracted away from the normal
A ray of light passes from a medium X to another medium Y. No refraction of light occurs if the ray of light hits the boundary of medium Y at an angle of:
(a) 0°
(b) 45°
(c) 90°
(d) 120°
Water is optically denser than glass.
A ray of light when passes from glass to air, bends towards the normal.
When a ray of light travels from water to air, it bends ............. the normal.
What do you understand by refraction of light?
Draw suitable diagrams to illustrate how a beam of light incident parallel to the principal axis is reflected by:
(a) a concave mirror, and (b) a convex mirror
Light enters from air to glass having refractive index 1.50. What is the speed of light in the glass? The speed of light in vacuum is 3 × 108 m s−1.
Due to _______ pencil looks bent in water, in the given experiment.
Identify the wrong figure from the following.
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.
Explain with diagrams how refraction of incident light takes place from
- rarer to denser medium
- denser to rarer medium
- normal to the surface separating the two media.
If a beam of red light and a beam of violet light are incident at the same angle on the inclined surface of a prism from air medium and produce angles of refraction r and v respectively, which of the following is correct?
The phenomenon of light passing through the object is called ______.
How does the light travel?
Twinkling of stars and Mirage are the two phenomena occurring due to refraction.
The bottom of swimming pool appears to be less deep than the actual one because of
