What is the average velocity between t=0 sec and t=5 sec? 25 m/sec correct: your answer is correct. (b) what is the acceleration between t=0 sec and t=5 sec? 25 m/sec/sec incorrect: your answer is incorrect. (c) what is the average velocity between t=5 sec and t=8 sec? 20 m/sec incorrect: your answer is incorrect. (d) what is the acceleration between t=5 sec and t=8 sec? (e) what is the average velocity after t=8 sec? 0 m/sec correct: your answer is correct. (f) what is the acceleration after t=8 sec? 0 m/sec/sec correct: your answer is correct. (g) what is the total displacement during these ten seconds? 60 m correct: your answer is correct. (h) what is the total distance traveled during these ten seconds? 190 m correct: your answer is correct. (i) what is the average velocity during these ten seconds? 6 m/sec correct: your answer is correct. (j) what is the average speed during these ten seconds?

explanation:

as the height from which the ruler was dropped increased, the speed of the ruler at ryan's hand increased.

air exerts forces on falling objects near earth’s surface.

explanation:

the term 'free falls' refer to object that are falling towards the earth, in a situation in which gravity is the only force acting on the object.

for an object in free fall, the acceleration is constant (g, the gravitational acceleration), and so the velocity of the object constantly increases.

for objects near earth's surface, there is always another force acting on the object: the resistance due to the air. this force is opposed to the direction of fall of the object, and it is proportional to the velocity of the object, so as the object falls down, this force increases up to a point when it balances the force of gravity, and the object continues its motion at constant velocity (called terminal velocity). since in this case gravity is not the only force acting on the object, we are not in a situation of free fall.