How do you determine work done wi th just mass and distance?

AI Thread Summary
To determine the work done on a 28 kg object pushed 1.2 m, the formula W=Fd is used, where F is force and d is distance. The force can be calculated using F=ma, but without knowing the acceleration (a), the calculation remains incomplete. The discussion reveals that the correct answer of 1200 J assumes a specific acceleration that is not provided in the problem statement. Participants agree that additional information, such as acceleration or final velocity, is necessary to solve the problem accurately. The conversation emphasizes the importance of complete data in physics problems to arrive at a definitive answer.
crushedcorn
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1. The problem statement, all variables and given/Information

If a person pushes a 28 kg object 1.2 m, how much work did they just do?

Homework Equations


W=Fd
F=ma

The Attempt at a Solution


If W=Fd and F=ma, then W=(ma)d. The farthest I can get is W=28a*1.2=33.6a. Since the motion is horizontal, a=9.8 m/s2 wouldn't apply, so I am left with 2 variables and no answer. However, the correct answer is 1200 J. Where is this answer coming from?
 
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Out of the blue, as they say. Hello CC, and welcome to PF :smile: !

With the given information, there really is no telling. As you more or less conclude correctly.
There must be something else.
 
you would need atleast ##a## or final velocity. because for 1200J a= 35.7m/s², what if i choose a=1m/s². ill get a different answer.
So the question is incomplete.
 
Thank you and thank you! I felt like I was missing the entire concept. I feel much better :-)
 
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