Through which part of the lens the ray of light without suffering deviation and in which position is the object placed if a convex lens always gives real image?
Optical centre, focus
pole, focus
focus,beyond centre of curvature
Optical centre, beyond centre of curvature
Which of the following cannot be considered for the determination of the angle of deviation of a prism?
The refracting angle
The angle of incidence of the ray
The refractive index of the prism material
The thickness of the prism
If a lens gives a positive magnification greater than unity, then what type of image does it indicate?
Real and inverted image having smaller size than the object
Virtual and upright image having larger size than the object
Real and upright image having smaller size than the object
Virtual and inverted image having larger size than the object
An object is placed at a distance of 25cm from a convex lens whose focal length is 10cm. What will be the image distance?
50cm
16.66cm
6.66cm
10cm
Two thin lenses of power +5D and -2D are placed in contact with each other. What is the focal length of the combination?
+3m
-3m
+0.33m
-0.33
An object is placed at a distance of 30.0cm from a thin converging lens a long its axis. The lens has a focal length of 10.0cm. What are the values of the image distance and magnification (respectively)?
60.0 cm and 2.00
15.0 cm and 2.00
60.0 cm and 5.00
15.0 cm and -0.500
What happens when complementary colors are mixed together in equal amounts?
They produce a white color
They produce a black color
They produce a black or dark grey color
They produce a dark grey color
Which of the following is false with regard to optical radiation?
the wavelengths of visible light lie between 400nm and 780nm
ultraviolet A has a shorter wavelength than ultraviolet C
the human lens is better at absorbing shorter than longer wavelengths
eclipse burn is caused by infrared radiation
Which list is the correct primary color list?
blue, green, yellow
blue, red, yellow
red, blue, green
white, black, grey
A light ray in air enters and passes through a block of glass. What can be started with regard to its speed after it emerging from the block?
Speed is less than when in glass
Speed is less than before it entered glass
Speed is same as that in glass
Speed is same as that before it entered glass
