Did I Solve the Object Thrown Vertically Upwards Problem Correctly?

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An object is thrown vertically upwards at 72 km/h, and the problem asks how long it takes to reach a point 25 meters below the starting point, with gravitational acceleration set at 10 m/s². The original poster calculated the time as 4 seconds but noted that the correct answer is 5 seconds. After reviewing their work, they discovered an error in their calculations. The discussion highlights the importance of double-checking calculations in physics problems. The final conclusion is that the correct time to reach the specified point is indeed 5 seconds.
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Homework Statement



5. An object is thrown vertically upwards with a speed of 72 kilometres per hour. How long does it take to reach a point 25 meters below the starting point? You can take g as 10 ms-2 for convenience.

Here is my answer. I got 4 yet the answer is 5.

http://i.imgur.com/Ewvwh.jpg

http://i.imgur.com/ynVmM.jpg

http://i.imgur.com/OBVsX.jpg

Am I correct?

Homework Statement


Homework Equations


The Attempt at a Solution

 
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Darth Frodo said:

Homework Statement



5. An object is thrown vertically upwards with a speed of 72 kilometres per hour. How long does it take to reach a point 25 meters below the starting point? You can take g as 10 ms-2 for convenience.

Here is my answer. I got 4 yet the answer is 5.

[IMG ]http://i.imgur.com/Ewvwh.jpg[/PLAIN]

[IMG ]http://i.imgur.com/ynVmM.jpg[/PLAIN]

[IMG ]http://i.imgur.com/OBVsX.jpg[/PLAIN]

Am I correct?

Homework Statement



Homework Equations



The Attempt at a Solution

Please reduce the size of your images.
 
Ah, Nevermind error found
 

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