If an object is accelerating, its speed must be changing. True False

False

Explanation:

an accelerating objects could be changing their speed; but it is also possible that an accelerating object is only changing its direction while maintaining a constant speed.

Hope that helped :)

answer : a model is often used to explain and make things easier to understand when any scientific topic needs to be demonstrated and explained.

as in this case where a scientist wants to use a model to present the results of his detailed scientific investigation. he should do it as it will him to make the audience understand the concept in a much better way. also, it can be changed according to new scientific understandings.

in the analysis of systems that involve fluid flow, we frequently encounter the combination of properties u and pv.