# Anyone help please

Can anyone solve me these questions, please

1. A convergent lens has one 8 cm focal length. One places a 2 cm height object at 4 cm of his optical center. Find the various characteristics of the image obtained.

2. A divergent lens has one 8 cm focal length. One places a 2 cm height object at 4 cm of his optical center. Find the various characteristics of the image obtained.

3. One observes a star with a telescope. This one is provided with a concave mirror having a radius of curvature of 3.0m. Where is the image formed by this mirror?

4. A 5 cm height object is placed in front of a convex mirror. Why the image of this object can't measure 8 cm?

5. One places a 2 cm height candle in front of a convergent lens of which focal length is of 4 cm. The image obtained has a 4 cm height. Which is the exact position of the candle and the image?

6. A convergent lens has one 12 cm focal length. With this lens, one obtains a real image of which the height is triple of that of the object. Where are the object and the image?

7. The distance minimum of vision distinct from a person presbyope is of 100 cm. Calculate the focal length of the corrective lenses which are necessary to read for him of 25 cm.

8. A myope cannot clearly see the objects distant of more than 1 m of his eyes. Which is the focal length of the lenses which will enable him to see very distant objects.

9. Focal length of the objective: 1 cm
Focal length of the eyepiece: 5 cm
Outdistance between the objective and the eyepiece: 25 cm
Height of the object: 0.1 mm
Outdistance between the object of the objective: 1.05 cm
a) To make a diagram.
b) Calculate the position and the size of the image formed by the objective.
c) Calculate the position and the size of the image formed by the eyepiece. (Note that in this case, the object is the image formed by the objective.) ** the sentence does not do much direction, the writing was too pale I could not retranscribe the bracket correctly.)

10. One places oneself at 12 cm of a 6 m height tree to photograph it. When the image is very clear, the distance between the film and the optical center of the objective (a convergent lens) is of 8.75 cm.

11. Imagine that you have a camera whose objective has one 5 cm focal length. Your apparatus makes it possible to photograph objects located between 50 cm and the infinite one. Calculate the distances maximum and minimal between the film and the optical center of the objective.

Thank you