A person can see well in the distance, but cannot do so at an arm's-length distance. To correct this, lenses that are ________ having a ________ power could be used
a. thicker at their center than at the edges, positive
b. thicker at their center than at the edges, negative
c. thinner at their center than at the edges, positive
d. thinner at their center than at the edges, negative
a
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A stone is dropped from the top of a well that has water in it at a depth of 30.0 m. How long does it take the stone to reach the water?
In a given LC resonant circuit,
A) the stored electric field energy is greater than the stored magnetic field energy. B) the stored electric field energy is less than the stored magnetic field energy. C) the stored electric field energy is equal to the stored magnetic field energy. D) all of the given answers are possible.
A brass cube, 13.0 cm on a side, is raised in temperature by 239°C. The coefficient of volume expansion of brass is 57 × 10^?6/C°. By what percentage is any one of the 13.0-cm edges increased in length?
a. 0.34% b. 5.9% c. 0.45% d. 1.8% e. 4.3%
An FM radio station broadcasts at 98.6 MHz. What is the wavelength of the radiowaves?
a. 60.8 m b. 6.08 m c. 3.04 m d. 0.314 m e. 0.33 cm