Final answer:
The period of a wave displayed on an oscilloscope with a time setting of 20 microseconds per centimeter and a trace length of 7.5 centimeters is 150 microseconds.
Step-by-step explanation:
The subject of this question is physics, specifically relating to the concepts of time period and frequency in the context of wave oscillations. The question asks about determining the period of a wave displayed on an oscilloscope.
The oscilloscope's seconds/division setting is 20 microseconds per centimeter. If the trace on the oscilloscope is 7.5 centimeters long, we can calculate the period of the wave represented by the trace by multiplying the length of the trace by the time represented by each centimeter:
Period (T) = length of trace × seconds/division
T = 7.5 cm × 20 microseconds/cm
T = 150 microseconds
Thus, the period of the wave is 150 microseconds.