when an object of height 1 cm is kept at a distance 4 cm from a concave mirror,its erect image of height 1.5 cm is formed at a distance 6 cm behind the mirror.find the focal length of mirror
Hello Isani Saha, recall formula 1/u + 1/v = 1/f
As per cartesian sign convention, u = - 4 and v = 6 and f = -ve
Plug -1/4 + 1/6 = -1/f
Or - 1/12 = -1/f
==> f = 12 cm
As per cartesian sign convention, u = - 4 and v = 6 and f = -ve
Plug -1/4 + 1/6 = -1/f
Or - 1/12 = -1/f
==> f = 12 cm