Consider the optically denser lenses P, Q, R and S drawn below. According to Cartesian sign convention which of these have positive focal length?
A. OnlyP
B. Only P and Q
C. Only P and R
D. Only Q and S
Answer:B
Consider the optically denser lenses P, Q, R and S drawn below. According to Cartesian sign convention which of these have positive focal length?
A. OnlyP B. Only P and Q C. Only P and R D. Only Q and S