Give example from everyday life in which an object’s acceleration is pointed upward and the object is a)speeding up and b) slowing down?

2 Answers
Feb 3, 2018

Rockets and ballistics.

Explanation:

As long as sufficient force remains applied, a rocket continues to accelerate upward. A ballistic projectile of any type is no longer powered, and the force of gravity reduces the upward acceleration until it finally ends the upward motion.

Feb 7, 2018

Standing up offers an example of case a. Sitting down offers an example of case b.

Explanation:

OK, 2 cases with acceleration vector pointing upward.

In case a), the object is speeding up.
A rocket is one example but some might question whether that is an example from everyday life. (Even though Elon Musk launched his Falcon Heavy today.)

So I suggest that when you stand up from a sitting position offers an example from everyday life. Consider when you have just started getting up. You will have started moving, your speed is slow but increasing -- increasing because your acceleration is pointing upward.

In case b), the object is slowing down.
Let's have you sit down now. You accelerate toward your chair, but when you are getting close to the chair you want to slow your descent so you don't hit the chair too hard. Your speed is downward, but in order to slow down, your acceleration needs to be upward to reduce your downward speed.

I hope this helps,
Steve