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Suppose a camera鈥檚 exposure is correct when the lens has a focal length of 8.0 mm. Will the picture be overexposed, underexposed, or still correct if the focal length is 鈥渮oomed鈥� to 16.0 mm without changing the diameter of the lens aperture? Explain

Two converging lenses with focal lengths of $40cm$and $20cm$are $10cm$apart. A $2.0cm$tall object is $15cm$in front of the$40cm$focal-length lens.

a. Use ray tracing to find the position and height of the image. Do this accurately using a ruler or paper with a grid, then make measurements on your diagram.

b. Calculate the image position and height. Compare with your ray-tracing answers in part a.

Two converging lenses with focal lengths of 40 cm and 20 cm are 10 cm apart. A 2.0-cm-tall object is 15 cm in front of the 40-cm-focal-length lens. a). Use ray tracing to find the position and height of the image. Do this accurately using a ruler or paper with a grid, then make measurements on your diagram.

b). Calculate the image position and height. Compare with your ray-tracing answers in part a.

Suppose you wanted special glasses designed to let you see underwater without a face mask. Should the glasses use a converging or diverging lens? Explain.

Ellen wears eyeglasses with the prescription$-1.0D$.

a. What eye condition does Ellen have?

b. What is her far point without the glasses?

A magnifier has a magnification of $5x$. How far from the lens should an object be held so that its image is seen at the near-point distance of $25cm$? Assume that your is immediately behind the lens.

A microscope has a $20cm$tube length. What focal-length objective will give total magnification localid="1649845070556" $500脳$when used with an eyepiece having a focal length $5.0cm$?

A standardized biological microscope has an $8.0mm$focal length objective. what focal-length eyepiece should be used to achieve a total magnification of$100x$?

A converging lens with a focal length of $40cm$and a diverging lens with a focal length of $-40cm$are $160cm$apart. A $2cm$tall object is $60cm$in front of the converging lens.

a. Use ray tracing to find the position and height of the image. Do this accurately using a ruler or paper with a grid, then make measurements on your diagram.

b. Calculate the image position and height. Compare with your ray-tracing answers in part a.

A sheet of glass has $n_{red}=1.52$ and $n_{violet}=1.55$. A narrow beam of white light is incident on the glass at $30掳$. What is the angular spread of the light inside the glass?