Question

The image of an object placed at 60cm in frost of a lens is
obtained on a screen at a distance of 120cm from it. Find the
focal length of the lens. What would be the height of the image
if the object is 5cm high?
​

Answer 1

Explanation:

ANSWER

Object distance u=−60 cmImage distance v=+120 cmUsing lens formula,1/f=1/v−1/u1/f=1/120−(−1/60)=+40cmH(image) / H(object) = v/uHi=−120/60X5=−10cm