Question

An object 5 cm in length is held 25 cm away from covrging lens of focal length 10 cm. Draw the ray diagram and find the position,size and the nature of the image formed

Answer 1

Given,

The lens is converging or convex lens

Hence we have=>

Height of object, Ho = 5cm

Object distance, u = -5cm

Focal length = 10cm

(since it is a convex lens hence by new Cartesian sign conversation its positive)

Plz refer to the attachment for the ray diagram and the numericals are down below.

Now, by using lens formula=>

1/v - 1/u = 1/f

=>1/v= (1/10)- (1/5)

=>1/v = (1-2)/10

=>v = -10cm.

Hence we get that=>>>

v = u =-10cm.

Hence image formed is=>

1)Real and inverted

2)Same sized

3)Formed on right side of lens.

4)The image and object are at same distance from lens.

Remember

1)New Catesian Sign convention for both mirror and lens

2)Mirror formula

1/v + 1/u = 1/f

3) Lens Formula

1/v - 1/u = 1/f