Question

An object of size 7cm is placed at 27cm in front of a concave mirror bearing focal length of 18 cm . Find the position, size and nature of the image . plz answer this in no time

Answer 1

h=7cm
u= -27cm
f= -18cm
v=?

1/f=1/v+1/u
1/v=(1/-18) + (1/27)
V=54cm
h'=14cm
Virtual, Erect.

Answer 2

u= -27cm
f = -18cm
h (object) = 7cm

Now, 1/v +1/u = 1/f
1/v + 1/-27 = 1/-18
1/v = 1/-18+1/27
1/v = 1/54
v= 54

We know that,
h(I)/h(o) = -v/u
h(I)/7 = -54/-27
h(I) = 54*7/27
h(I) = 14 cm

Nature- Virtual and erect