Can you please check if my answers are correct?

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The discussion revolves around verifying answers to physics homework problems involving motion under constant acceleration and free fall. The first problem correctly calculates the speed at the end of 5 seconds as 40 m/s and the average speed as 20 m/s. For the second problem, the time to reach the highest point is accurately noted as 5 seconds, and the distance traveled is correctly calculated at 122.5 m. However, the time before the stone hits the water is questioned, as the provided answer of 12.24 seconds is deemed incorrect, and there is confusion regarding the interpretation of the question about speed. Overall, the responses are mostly correct, with a need for clarification on specific points.
honestliar
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Homework Statement


An object starts from rest w/ a constant acceleration of 8m/s^2 along straight line.
a)find the speed at the end of 5 sec.------40sec
b)the ave. spped for the sec interval------20m/s

A stone is thrown vertically upward w/ an initial velocity of 49m/s
a)How long does it take to reach the highest point-----5 sec
b)How far does the stone go---122.5m
c)How fast does the stone go----4.52s



A stone is dropped from a bridge w/c is 60m above seal level. a)find the time before it hits the water----12.24s
b)Speed upon hitting the water---34.29m/s


thanks
 
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Hi honestliar! :smile:

They're ok except for …
honestliar said:
a)find the time before it hits the water----12.24ss

(and I don't understand the question "c)How fast does the stone go" :confused:)
 

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