Exam 25: Optical Instruments

Diego is nearsighted and cannot see things beyond 110 cm from his eyes. What is the focal length of the contact lenses that will enable him to comfortably see distant hills clearly?

If a metal sheet containing a tiny hole is heated (without damaging it) and therefore expands, what happens to the angular location of the first-order diffraction maximum?

What is the minimum distance between two points on the Moon that could be just resolved by the Keck telescope in Hawaii using a wavelength of 600 nm and having perfect optics? The diameter of this telescope mirror system is 10 m, and the distance to the Moon is 380,000 km.

A simple digital camera lens with focal length $f _ { O } = 3.00 \mathrm {~cm}$ perfectly focuses the image of an object on a CCD sensor located a distance $14.00 \mathrm {~cm}$ away from the lens. The object now moves away from the lens and the new distance between the lens and sensor is $13.00 \mathrm {~cm}$ . (a) By what amount did the object change its distance from the lens? (b) What is the new magnification?

Nearsightedness is usually corrected with

A person's hyperopic (farsighted) eye can focus on objects that are 75 cm away and farther. What power and what focal length contact lenses should be prescribed so this person can see objects 25 cm and farther from the eye?

Light from a He-Ne laser of wavelength 633 nm passes through a circular aperture. The resulting pattern is observed on a screen 4.0 m behind the aperture, where the width of the central bright Circle is 1.1 cm. What is the diameter of the hole?

The length of a telescope is 1.60 m and it has a magnification of 60.0. What is the focal length of the eyepiece?

Which one of the following is normally not a characteristic of a simple two-lens refracting astronomical telescope?

A nearsighted person has a far point of 50 cm for his right eye and 150 cm for his left eye. For each eye, what power contact lens will allow the person to see gorgeous sunsets?

The distance between the object to be viewed and the eyepiece of a compound microscope is 25.0 cm. The focal length of its objective lens is 0.200 cm and the eyepiece has a focal length of 2.60 cm. What is the magnitude of the total magnification of the microscope when used by the person of Normal eyesight if it is designed for minimum eyestrain?

A camera lens having a 50-mm focal length is set to f/4.0. What is the minimum spacing of two objects located 12 m from the lens if the objects are just barely resolved in the image using light of Wavelength 500 nm?

The pupil of a person's eye changes from a diameter of 3.5 mm to 1.5 mm as the illumination is increased. By what factor does the minimum angle of resolution change?

The objective lens of a refracting astronomical telescope has a focal length of 60 cm, and the eyepiece has a focal length of 2.0 cm. How far apart should the lenses be placed in order to form a Final image at infinity?

A compound microscope has an objective with a focal length of 3.00 mm and an eyepiece of focal length 6.00 cm. It is adjusted for minimum eyestrain for persons with a near point of 25 cm. If the Two lenses are separated by 40.0 cm, what is the total overall magnification?

The near point of a farsighted person is 65 cm. What power contact lens must he use to correct this problem and be able to read a book at a normal near point of 25 cm?

A student constructs an astronomical telescope with a magnification of 10. If the telescope has an objective lens of focal length 0.50 m, what is the resulting length of the telescope?

What power contact lens is needed to correct for farsightedness where the uncorrected near point is 75 cm?

The focal length of the lens of a simple film camera is 40.0 mm. By what amount should the distance between the lens and the film be increased or decreased to change the focus from a Person who is 25 m from the lens to one who is 4.0 m from the lens?

The objective lens and the eyepiece of a microscope have focal lengths of 4.0 mm and 25 mm, respectively. The objective produces a real image 30 times the size of the object, with the final Image viewed at infinity. The near point of the microscope user is at 25 cm. What is the magnitude Of the overall magnification of the microscope?