Final answer:
The amplitude of one wave is affected by the amplitude of another only if they are exactly aligned, which is true. The position vs time graph of a speeding object is not a straight line, which means that statement is false. Waves can superimpose even if their frequencies are different, making that statement true.
Step-by-step explanation:
The amplitude of one wave is affected by the amplitude of another wave only when they are precisely aligned. This concept is referred to as constructive or destructive interference and happens because of the principle of superposition. This statement is True, as the amplitudes of waves directly influence each other during their overlap. When two waves meet, they temporarily add together; if their crests align (constructive interference), the resultant wave has a higher amplitude, and if a crest of one wave aligns with a trough of another (destructive interference), they can cancel each other out, resulting in a reduced amplitude.
The position vs time graph of an object that is speeding up is not a straight line because the slope of the graph represents the velocity, and if the velocity is changing, then the slope is also changing. Therefore, this statement is False. The graph would be a curve, reflecting the increase in velocity over time.
The average speed of an object can be different from the average velocity when the direction of the motion changes. Since speed is scalar and does not consider direction, whereas velocity is a vector and does consider direction, if an object returns to its starting point, its displacement is zero, therefore its average velocity is zero, but its average speed is greater than zero because it still covered distance. Thus, it can be True that the average speed is greater than the average velocity if the motion involves a change in direction.
Waves can superimpose even if their frequencies are different. The superposition principle states that when two or more waves pass through each other, their displacements at any point are additive. This is True; the resultant wave is a combination of all the individual waves, regardless of their frequency.