Exam 35: Optical Instruments

What is the angular magnification of a magnifying glass of focal length 4.0 cm if the image is to be viewed by a relaxed eye (image at the far point)having a near point of 25 cm and a far point at infinity?

What is the focal length of the corrective contact lens needed by a nearsighted person whose far point is 60 cm?

The focal length of a thin lens is 40 mm and its aperture diameter is 10 mm.What is the f-number of this lens?

A person having a near point of 25 cm and a far point at infinity uses a converging lens of focal length 5.0 cm as a magnifying glass.What is the magnification if the person's eye is relaxed (with the image at his far point)?

An astronomical telescope has an objective of diameter 20 cm with a focal length of 180 cm.The telescope is used with an eyepiece of focal length 30 mm.What is the angular magnification of this telescope?

Which one of the following is a characteristic of a compound microscope?

What power contact lens must be used to correct the vision of a nearsighted person whose far point is 40 cm?

You have available lenses of focal lengths 2.0 cm,4.0 cm,8.0 cm,and 16.0 cm. (a)If you were to use any two of these lenses to build a telescope,what is the maximum magnification you could achieve? (b)If you were to use any two of these lenses to build a telescope,what is the lens separation for the maximum magnification telescope?

The focal lengths of the objective and the eyepiece of a microscope are 0.50 cm and 2.0 cm,respectively,and their separation adjusted for minimum eyestrain (with the final image at the viewer's far point)is 6.0 cm.The near point of the person using the microscope is 25 cm and the far point is infinity. (a)If the microscope is focused on a small object,what is the distance between the object and the objective lens? (b)If the microscope is focused on a small object,what is its final magnification?

A lens is designed to work in the visible,near-infrared,and near-ultraviolet.The best resolution of this lens from a diffraction standpoint is

The objective and the eyepiece of a refracting astronomical telescope have focal lengths of 320 cm and 4.0 cm,respectively.The telescope is used to view Neptune and the final image is set at infinity.The diameter of Neptune is 4.96 × 10⁷ m and the distance from the earth at the time of observation is 4.4 × 10¹² m.What is the angle (in mrad)subtended by the final telescopic image of Neptune?

The focal lengths of the objective and the eyepiece in a microscope are 0.290 cm and 2.50 cm,respectively.An object is placed 0.300 cm from the objective.The image of this object is viewed with the eyepiece adjusted for minimum eyestrain (image at the far point of the eye)for a person with normal vision.What is the distance between the objective and the eyepiece?

The near point of a person's uncorrected eyes is 125.0 cm and the far point is at infinity.What is the focal length of a contact lens that will move the near point to 25.0 cm from this person's eyes?

What is the limiting angle of resolution for the eye if the pupil diameter of the eye is 4.0 mm,the wavelength of the light is 600 nm,and index of refraction of the liquid in the eye is 1.34?

A ray of light consisting of blue light (wavelength 480 nm)and red light (wavelength 670 nm)is incident on a thick piece of glass at 80°.What is the angular separation between the refracted red and refracted blue beams while they are in the glass? (The respective indices of refraction for the blue light and the red light are 1.4636 and 1.4561.)

Light consisting of a mixture of red and blue light enters a 40°,70°,70° prism along a line parallel to the side opposite the 40° vertex.The index of refraction of the prism material for blue light is 1.530,and for red light it is 1.525.What is the angle between the two emerging beams of light?

A man is nearsighted and cannot see things clearly beyond 110from his eyes.What is the focal length of the contact lenses that will enable him to see very distant objects clearly?

A camera used for aerial surveillance has a lens with a 30-cm maximum aperture and a 42-cm focal length.Assume light of 550-nm wavelength is used and that the resolution of the camera is limited solely by diffraction.What is the angular resolution of the camera at maximum aperture?

A nearsighted physicist cannot see things clearly beyond 90 cm from her eyes.What is the power of the contact lenses that will enable her to see very distant objects clearly?

The distance between the object 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.A person with a near point of 25.0 cm and a far point at infinity is using the microscope. (a)What is the angular magnification obtainable using the eyepiece alone as a magnifying lens if the final image is at the person's far point? (b)What is the total magnification of the microscope when used by the person of normal eyesight?