Question

If the object is placed at 100 cm from convex lens then find the location nature and size of image when focal length is 50cm

Answer 1

Answer

Given

Object distance, u = -100cm

focal length, f = +50cm

By using lens formula,

1/f = 1/v - 1/u

=> 1/v = 1/f + 1/u

=> 1/v = 1/50 + 1/-100

=> 1/v = 1/50 - 1/100

=> 1/v = 1/100

=> v = +100cm

Since the magnitude is same, the size of the image formed will be same as the object

But the image will be formed behind the lens due to it's (+ve) sign

So, the image will be virtual and erect