You wish to read from a single lightbulb in a lamp at your desk. In order to get the same brightness on the page from a 25 W bulb as you can from 100 W bulb, how much closer do you need to bring the lamp to your book? Assume that the light bulbs are equally efficient.
A. 1/2 the distance
B. 1/8 the distance
C. 1/4 the distance
D. 1/16 the distance
A. 1/2 the distance
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All the statements below are true. Which one gives the primary reason why the surface of Venus today is some 450°C hotter than the surface of Earth?
A) Venus has a much stronger greenhouse effect than Earth. B) Venus is only about 73% as far from the Sun as Earth. C) Venus has a much higher reflectivity than Earth. D) Venus has a higher atmospheric pressure than Earth.
Genetic modification has met with much more resistance in Europe than in the United States
Why should the Europeans be so against the use of genetically modified organisms (GMO)? Why are Americans less opposed to use of GMO? Are you personally for or against use of GMO? Explain as best you can with the facts available.
Consider the hypothetical discovery from Part A reading: "A star's 5 terrestrial planets orbit in the opposite direction of its 3 jovian planets." This discovery would be inconsistent with the nebular theory because the theory holds that __________.
a. terrestrial planets should orbit in a different plane from the plane of the jovian planets b. all the planets formed in a rotating, disk-shaped nebula c. star systems should have equal numbers of terrestrial and jovian planets
Torques T 5 5.7 kN # m are applied to a hollow aluminum shaft (G 5 27 GPa and d1 5 52 mm). The allowable shear stress is 45 MPa and the allowable normal strain is 8.0 3 1024. The required outside diameter d2 of the shaft is approximately:
(A) 38 mm
(B) 56 mm
(C) 87 mm
(D) 91 mm