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What type of eyeglasses should a nearsighted person wear?
A. diverging lenses
B. bifocal lenses
C. converging lenses
D. plano-convex lenses
E. double convex lenses
A. diverging lenses
A. diverging lenses
See lessAn object is 2 m in front of a plane mirror. Its image is:
A. virtual, inverted, and 2 m behind the mirror
B. virtual, inverted, and 2 m in front of the mirror
C. virtual, erect, and 2 m in front of the mirror
D. real, erect, and 2 m behind the mirror
E. none of the above
E. none of the above
E. none of the above
See lessWhich instrument uses a single converging lens with the object placed just inside the focal point?
A. Camera
B. Compound microscope
C. Magnifying glass
D. Overhead projector
E. Telescope
C. Magnifying glass
C. Magnifying glass
See lessA man holds a rectangular card in front of and parallel to a plane mirror. In order for him to see the entire image of the card, the least mirror area needed is:
A. that of the whole mirror, regardless of its size
B. that of the pupil of his eye
C. one-half that of the card
D. one-fourth that of the card
E. an amount which decreases with his distance from the mirror
D. one-fourth that of the card
D. one-fourth that of the card
See lessA card marked IAHIO8 is standing upright in front of a plane mirror. Which of the following is NOT true?
A. The image is virtual
B. The image shifts its position as the observer shifts his position
C. The image appears as 8OIHAI to a person looking in the mirror
D. The image is caused mostly by specular rather than diffuse reflection
E. The image is the same size as the object
B. The image shifts its position as the observer shifts his position
B. The image shifts its position as the observer shifts his position
See lessA convex spherical refracting surface separates a medium with index of refraction 2 from air. The image of an object outside the surface is real:
A. always
B. never
C. only if it is close to the surface
D. only if it is far from the surface
E. only if the radius of curvature is small
D. only if it is far from the surface
D. only if it is far from the surface
See lessA convex refracting surface has a radius of 12 cm. Light is incident in air (n = 1) and refracted into a medium with an index of refraction of 2. To obtain light with rays parallel to the central axis after refraction a point source should be placed on the axis:
A. 3 cm from the surface
B. 6 cm from the surface
C. 12 cm from the surface
D. 18 cm from the surface
E. 24 cm from the surface
C. 12 cm from the surface
C. 12 cm from the surface
See lessThe image produced by a convex mirror of an erect object in front of the mirror is always:
A. virtual, erect, and larger than the object
B. virtual, erect, and smaller than the object
C. real, erect, and larger than the object
D. real, erect, and smaller than the object
E. none of the above
B. virtual, erect, and smaller than the object
B. virtual, erect, and smaller than the object
See lessA nearsighted person can see clearly only objects within 1.4 m of her eye. To see distant objects, she should wear eyeglasses of what type and focal length?
A. diverging, 2.8 m
B. diverging, 1.4 m
C. converging, 2.8 m
D. converging, 1.4 m
E. diverging, 0.72 m
B. diverging, 1.4 m
B. diverging, 1.4 m
See lessAn erect object is placed on the central axis of a thin lens, further from the lens than the magnitude of its focal length. The magnification is +0.4. This means:
A. the image is real and erect and the lens is a converging lens
B. the image is real and inverted and the lens is a converging lens
C. the image is virtual and erect, and the lens is a diverging lens
D. the image is virtual and erect, and the lens is a converging lens
E. the image is virtual and inverted and the lens is a diverging lens
C. the image is virtual and erect, and the lens is a diverging lens
C. the image is virtual and erect, and the lens is a diverging lens
See less