convex lens

concave lens

biconcave lens

both B and C

real, inverted and enlarged

virtual, upright and reduced

real, inverted and reduced

virtual, erect and enlarged

at the focal point.

at a point half way to the focal point.

at the centre of curvature.

at infinity.

X = focus, Y = optical centre, Z = centre of curvature

X = centre of curvature, Y = focus, Z = optical centre

X = centre of curvature, Y = optical centre, Z = focus

real, inverted and diminished

real, inverted and magnified

real, erect and magnified

real, inverted and same size

virtual, erect and magnified

the same as its angle of incidence. 

less than its angle of incidence. 

can be more or less than its angle of incidence. 

more than its angle of incidence. 

frequency.

wavelength.

speed.

all of these.

intensity

a vacuum.

warm air.

cool air.

frequency is greater in air than in glass. 

travels at the same speed in air and in glass. 

travels slower in glass than in air. 

frequency is greater in glass than in air.