Question

A tarantula of height h sits cautiously before a spherical mirror whose focal length has

absolute value | f | = 40 cm. The image of the tarantula produced by the mirror has the

same orientation as the tarantula and has height hꞌ= 0.20h.

(a) State with reasons, the image location and determine whether it is real or not.

(b) Determine the focal length f (sign included) of the mirror and hence deduce whether it

is a concave or convex mirror.

Answer 1

a)

if $h'<h$ and the image has the same orientation, than the mirror is convex, the image is not real,

b)

$f=-|f|=-40~\text {cm}.$