Exam 33: Lenses and Optical Instruments

A meniscus lens is made with the radius of curvature of the convex surface being 25.0 cm and the concave surface 45.0 cm. If the glass used has index of refraction 1.50, what is the focal length of this lens?

It is desired to project an image of an object four times actual size with a lens of focal length 20 cm. What object distance should be used?

An object is placed 10 cm from a convex lens of focal length 20 cm. What is the magnification?

If a person's eyeball is too short from front to back, the person is likely to suffer from

A magnifying glass can be made from a diverging lens.

A thin converging lens is found to form an image of a distant building 24 cm from the lens. If an object is placed 16 cm from the lens, how far from the object will the image be?

The focal lengths of the objective and eyepiece in a compound microscope are 0.50 cm and 2.00 cm, respectively. An object is placed at a distance of 0.52 cm from the objective. If the final image seen by the eye is at a distance of 25 cm from it, what is the magnification?

A camera lens that acts like a telescope to magnify images is referred to as a

The distance between the object and the eyepiece of a compound microscope is 18.0 cm. The focal length of its objective lens is 0.80 cm and the eyepiece has a focal length of 2.3 cm. The near-point distance of the person using the microscope is 25.0 cm. What is the total magnification of the microscope?

A nearsighted person has her distant vision corrected using a -2.0 D lens. Her uncorrected near point is 15 cm. What is her near point using this lens if the lens is 2.0 cm from the eye?

An object is placed 100 cm in front of a lens of focal length 20 cm. A second lens is placed 35 cm beyond the first, this second lens having a focal length of 8.0 cm. If the size of the object is 6.0 cm, what is the size of the final image?

The focal length of the lens of a simple camera is 40.0 mm. How far must the lens be moved to change the focus of the camera from a person 25 m away to one that is 4.0 m away?

Spherical mirrors suffer from

Jill is farsighted and cannot see objects clearly that are closer to the eye than 80.0 cm. What is the focal length of the contact lenses that will enable her to see objects at a distance of 25.0 cm from her eyes?

A student constructs an astronomical telescope with a magnification of 10. If the telescope has a converging lens of focal length 50 cm, what is the resulting length of the telescope?

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 3.0 cm. The magnifying power of the telescope is

A 4.0 cm tall object is placed 60 cm away from a converging lens of focal length 30 cm. What is the nature and location of the image?

A far sighted person can not see clearly objects that are closer to his eyes than 60.0 cm. Which one of the following combinations represents the correct focal length and the refractive power of the contact lenses that will enable him to see the objects at a distance of 25.0 cm from his eyes?

The image formed by convex lenses are

The images formed by concave lenses