The resistance of a copper wire increases if it is heated and decreases if it is cooled. what will happen to a circuit made of copper wire if the temperature drops from 40°c to 20°c?
a. the current, voltage, and resistance will all increase.
b. the voltage and the resistance will remain constant.
c. the current will increase and the resistance will decrease.
d. the resistance will increase and the voltage will remain constant.

Total solidification times of three casting geometries are to be compared: a sphere, a cylinder, in which the length-to-diameter ration - 1.0, and a cube. volume = 1000 cm^3 for all three shhapes, and the same casting alloy is used. a) determine the solidification times of each geometry b) based on the results of part (a), which geometric element would make the best riser? c) if the mold constant = 3.5 min/cm^2 in chvorinov's rule, compute the total solidification time for each casting.

An isotope undergoes radioactive decay by emitting radiation that has a –1 charge. what other characteristic does the radiation have?

The energy produced as a result of this flow of electrons from atom to atom is called