Test Mode
Reading
Mode
Right = 0
Wrong = 0
behind the principal focus
a distance larger than 2 f on the same side as the object
a distance between f and 2 f behind
a distance beyond 2 f behind
Both length and cross sectional area are double
Both length and radius are soubled
Only the length is increased
Cross sectional areas reduced
Concave lens of focal length 50 cm
Concave lens of focal length 25 cm
Convex lens of focal length 50 cm
Convex lens of focal length 25 cm