Sign rules (from your book) S>0 when object is on the incoming side of the lens or mirror S’>0 when the image is on the outgoing side of the lens or mirror (For a mirror, the incoming and outgoing sides are the same) R>0 when the center of curvature is on the outgoing side of the lens or mirror. (R<0 if it is on the OTHER side, which for a mirror, is NOT the incoming side!) m>0 image is erect, m<0 when inverted.

A double convex lens has its incoming surface with a radius of 20 cm and its outgoing surface with a radius of 10 cm. What are the correct signs of these two radii? A] both + B] both – C] incoming +, outgoing – D] incoming -, outgoing +

A double convex lens has its incoming surface with a radius of 20 cm and its outgoing surface with a radius of 10 cm. Which focal point is farther away from the lens? A] the incoming focal point B] the outgoing focal point C] both are the same distance

A double convex lens has its incoming surface with a radius of 20 cm and its outgoing surface with a radius of 10 cm. If this lens were immersed in water, what would happen to the focal length? A] it would get longer B] it would get shorter C] it would be unchanged

Magnifying Glass

You are examining a gem using a magnifier. If you switch to a magnifier with twice the focal length: A] you have to hold the gem at twice the distance and the magnification is doubled B] you have to hold the gem at half the distance and the magnification is doubled C] you have to hold the gem at twice the distance and the magnification is halved D] you have to hold the gem at half the distance and the magnification is halved

Camera

Eyeglasses

Microscope

Telescope

Young’s Experiment