Which has the larger light-gathering power?
a. a telescope of 5 cm diameter and focal length of 50 cm
b. a telescope of 6 cm diameter and focal length of 100 cm
c. a telescope of 2 cm diameter and focal length of 100 cm
d. a telescope of 3 cm diameter and focal length of 75 cm
e. both b and c since they have the same focal length.
b
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If you arrange the following 15 bits (111001111100111 ) into 5 rows of 3 bits starting with the first bit, what number does it spell out?
A) 2 B) 3 C) 5 D) 1
Suppose an artificial satellite has been put into circular orbit about the Earth, at a distance from the center of the Earth equal to 1/4 the distance from the Earth's center to the Moon's center. In terms of the Moon's period Tm, what will be the period of the satellite?
A. 8 Tm. B. Tm/16. C. Tm/8. D. 16 Tm. E. Tm.
For Laminar flow of a fluid through a circular duct of radius R, diameter D, constant wall temperature of Tw, and mean fluid temperature of T8 an expression for the temperature function is suggested to be
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