Physics:series of 3 lenses calculate mag

[ally.hady]

Homework Statement

An object is placed 10.0 cm from a series of 3 lenses. The first lens has focal length of 5.00 cm, the second lens has a focal length of 9.00 cm and the final lens has a focal length of 3.00 cm. the distance between each lens is 25.0 cm. Find the final position of the image and the overall magnification.

Homework Equations

1/f=1/Di + 1/Do

Di= distance to image, DO, distance to object. f= focal

The Attempt at a Solution

i don't know where to start here I am used to doing one lense questions please help

thanks.
Ally

 

[ehild]

Make a figure first. Then calculate the image distance from the first lens. The image will be the object for the second lens, find its distance from it and use as object distance in the lens equation to find the position of the second image which will be the object for the third lens.

ehild

 

[ally.hady]

Diagrams i thought of it before but it takes too much time and our teacher has allowed us to use diagrams on the test coming up but he also told us its not worth it due to the time distribution for all of the questions. do you think i can do this without drawing a diagram? forexample use the object to find images height then use that but the problem I am going to run into i think is the distance of 2ndobject (1st image) how am i going to calculate the distance of it? would it be x-25cm. the x representing the distance of image for the 1st lense? and the answer i get from x-25 would be distance of object for second lens? thankyou for taking the time to help appreciate it!

 

[ehild]

the problem I am going to run into i think is the distance of 2ndobject (1st image) how am i going to calculate the distance of it?

You can see that from a diagram at once.

ehild

 

[ally.hady]

thankyou sir