Final answer:
The average velocity of a body at the initial time t=0 with displacement given by s=5t² is zero since the body has not yet moved from its initial position.
Step-by-step explanation:
If the displacement of a body is given by s = 8t² - 3t², we first need to simplify the displacement equation. The equation simplifies to s = 5t². To find the average velocity over a time interval, we use the formula: average velocity = total displacement / elapsed time. However, when calculating the average velocity at the initial time t=0, the displacement is zero since the body has not moved yet, hence the average velocity is also zero.
During other intervals, for example from t=1 s to t=3 s, we would find the displacements at each time point (s(1) and s(3)) and divide by the time interval to get the average velocity between 1.0 s and 3.0 s. Keep in mind that this computation gives us a scalar quantity since we are working with one-dimensional motion. The direction would be implied from the sign of the average velocity.