3. (3 pts) A near-sighted person has a far point of 70 cm. What is the power of the lens needed to correct this eye so it can see objects far away (at infinity)? Assume that the lens is close to eye (contact lens)

A laboratory (astronomical) telescope is used to view a scale that is 300 cm from the objective, which has a focal length of 20.0 cm; the eyepiece has a focal length of 2.00 cm. Calculate the angular magnification when the telescope is adjusted for minimum eyestrain. Note: The object is not at infinity, so the simple expression m = fo/fe is not sufficiently accurate for this problem. Also, assume small angles, so that tan = .

What magnification will be produced by a lens of power 4.00 D (such as might be used to correct myopia) if an object is held 25.0 cm away?

Calculate the power at the eye when viewing an object 3.00 m away.

Find the distance between the objective and eyepiece lenses in the telescope in the above problem needed to produce a final image very far from the observer, where vision is most relaxed. Note that a telescope is normally used to view very distant objects.

The power for normal close vision is 54.0 D. In a vision-correction procedure, the power of a patient’s eye is increased by 3.00 D. Assuming that this produces normal close vision, what was the patient’s near point before the procedure?

How far from the lens must the film in a camera be, if the lens has a 35.0 mm local length and is being used to photograph a flower 75.0 cm away? Explicitly show how you follow the steps in the ProblemSolving Strategy for lenses.

A large reflecting telescope has an objective mirror with a 10.0 m radius of curvature. What angular magnification does it produce when a 3.00 m focal length eyepiece is used?

A camera with a 100 mm focal length lens is used to photograph the sun and mean. What is the height at the image of the sun on the film, given the sun is 1.40106km in diameter and is 1.50108km away?

The contact-lens prescription for a nearsighted person is —4.00 D and the person has a far point of 22.5 cm. What is the power of the tear layer between the cornea and the lens if the correction is ideal, taking the tear layer into account?