Question

for finding the focal length of a concave mirror by obtaining the image of a distant object, which one of the following would you like to focus?

(a) flame of a candle kept at the other end ofthe table

(b)any distant tree.

(c)window grill of the laboratory.

(d)a well lit distant tower.

plez give explanation for this question.......

Answer 1

we can use b,c,and d