Question

The focal length of a converging lens is 20 cm .An object is 60 cm from the lens .where Will the image be formed and what kind of image is it

Answer 1

f= 20
u= -60 (object is always placed at left)
APPLYING LENS FORMULA
1/f=1/v-1/u
Therefore 1/f+1/u=1/v
1/20 + 1/-60 =1/v
 (-60)+20/-60*20 (lcm)
-40/-1200 =1/v
v =1200/40
v = 30cm
m = v/u
m = 30/-60
m = -0.5