Resistance and Resistivity: You are given a copper bar of dimensions 3 cm × 5 cm × 8 cm and asked to attach leads to it in order to make a resistor. If you want to achieve the smallest possible resistance, you should attach the leads to the opposite faces that measure
A. 3 cm × 5 cm.
B. 3 cm × 8 cm.
C. 5 cm × 8 cm.
D. Any pair of faces produces the same resistance.
Answer: C
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The geocentric model was formulated before the heliocentric model.
a. true b. false
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The diffusion of atoms of similar size depends upon the presence of _____________.
Fill in the blank(s) with the appropriate word(s).