Who discovered by his experiments with glass prisms that white light consists of seven colours?
Newton
Brewster
Maxwell
Young
Instruments used in astronomical investigations are
microscopes
optical telescopes
radio telescopes
both (2) and (3)
The stars appear higher in the sky than they actually are, due to :
diffraction of light
scattering of light
refraction of light
reflection of light
A young man has to hold a book at arm's length to be able to read it clearly.The defect of vision is :
astigmatism
myopia
presbyopia
hypermetropia
The animals of prey have :
two eyes at the front
two eyes at the back
two eyes on the sides
one eye at the front and one on the side
The splitting up of white light in to seven colours on passing through a glass prism is called
Refraction
Diffraction
Dispersion
Scattering
We can see the sun before the actual sunrise by about :
5 minutes
2 minutes
2 hours
20 minutes
The sky appears to an astronaut in
blue colour
black
Indigo
white
With both eyes open, a person's field of view is about :
90°
150°
180°
360°
The least distance of distinct vision for a young adult with normal vision is about :
25 m
2.5 cm
25 cm
2.5 m
