Question 19M.3.SL.TZ2.11bii
| Date | May 2019 | Marks available | [Maximum mark: 2] | Reference code | 19M.3.SL.TZ2.11bii |
| Level | SL | Paper | 3 | Time zone | TZ2 |
| Command term | Calculate | Question number | bii | Adapted from | N/A |
A student places an object 5.0 cm from a converging lens of focal length 10.0 cm.
The student mounts the same lens on a ruler and light from a distant object is incident on the lens.
The image at I is the object for a second converging lens. This second lens forms a final image at infinity with an overall angular magnification for the two lens arrangement of 5. Calculate the distance between the two converging lenses.
[2]
the second lens has «cm» ✔
«so for telescope image to be at infinity»
the second lens is placed at 27 «cm»
OR
separation becomes 12 «cm» ✔
Only candidates who realised that a simple telescope was being constructed were able to answer the question correctly. Most candidates realised that the focal lenses need to be added but few found the focal lens of the second lens correctly.
