Christian Andreas Doppler's study of waves led him to conclude that as a wave source moves away from an observer, the frequency of the wave seems to decrease. If the source moves toward an observer, wave frequency increases. This
conclusion has been MOST useful to scientists who are -
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The a metal retainer that keeps the rolling elements evenly spaced. n a. seal n b. separator n c. bearing n d outer race

Will give brainliest! which statement best describes the similarities between fundamental forces? electromagnetic and strong nuclear forces influence the interaction between charged particles within an atom. gravitational and magnetic forces are both types of charges that occur in nature. nuclear and magnetic forces are both related to mass and weight. strong nuclear force is most like electrical force because they are both related to distance.

Is a copper wire a conductor or insulator?