Question

A 5 cm object is 18.0 cm from a convex lens, which has a focal length of 10.0 cm.

What is the distance of the image from the lens? Round your answer to three significant figures.


cm

What is the height of the image? Round your answer to three significant figures.


cm

Answer 1

The first one is 22.5

the second one is -6.25

Step-by-step explanation:

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Answer 2

1. Height of the object is 5 cm
The object distance (u) is 18 cm
The focal length is 10 cm
To calculate the image distance (v) we use;
1/f=1/v+1/u
1/v = 1/10-1/18
= 8/180
Therefore v = 180/8
= 22.5 cm

2. Height of the image
Magnification = v/u = Height of image/height of object
Therefore;
22.5/ 18= x/5
x = (22.5×5)/18
x = 6.25 cm
Therefore; the height of the image is 6.25 cm