JAMB - Physics (2005 - No. 3)
A thin converging lens has a power of 4.0 diopters determined its focal length.
2.50m
0.03m
5.00m
0.25m
คำอธิบาย
the power of a lens is defined as the reciprocal of the focal length ,expressed in metre.Mathematically, the power of a lens in dioptres is given by:(1)/f(in cm).
thus for lens of power of 4.0 dioptres we have that: (1)/(f) = +4.0
f= (1)/(4.0)
= 0.25cm
thus for lens of power of 4.0 dioptres we have that: (1)/(f) = +4.0
f= (1)/(4.0)
= 0.25cm