Final answer:
To determine the instantaneous velocity between 4s and 8s, one would typically need the velocity-time function or graph. Instantaneous velocity can be calculated using a derivative or the slope of the tangent on a velocity-time graph, or using the equation v = u + at for constant acceleration.
Step-by-step explanation:
To determine the instantaneous velocity of an object between 4 seconds (s) and 8 seconds (s), you would typically need information about the object's motion or a specific velocity-time graph. Instantaneous velocity is defined as the velocity of an object at a particular moment in time, and it can be found by taking the derivative of the position function with respect to time or by analyzing the slope of the tangent line to a point on the velocity-time graph.
Without the specific function or graph for the interval between 4s and 8s, it's not possible to give an exact value. However, if the motion is known to have a constant acceleration, the velocity could change linearly over time, and hence the instantaneous velocity at any point can be calculated if the initial velocity and acceleration are known.
For example, in one of the provided references, it is noted that a car accelerates uniformly from an initial velocity of 2 m/s to a final velocity of 10 m/s in 8 seconds. Based on that, the average acceleration can be found and then the instantaneous velocity at any point within that time frame can be calculated using the equation v = u + at, where v is the final velocity, u is the initial velocity, a is the acceleration, and t is the time.