Work problem. Right answer, wrong units

In summary, there is a question about finding the work needed to pump half the water out of a 2m x 1m x 1m aquarium filled with water. The density of water is 1000 kg/m3. The conversation also mentions a similar example in a book where units are added after computing the answer. The person initially thought the unit should be in Newtons, but later realizes it should be in Newton meters. The definition of work is also mentioned.
  • #1
tony873004
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My answer should obviously be in Newtons, but I'm getting Netwon meters.

An aquarium, 2 m long, 1 m wide, and 1 m deep is full of water. Find the work needed to pump half the water out of the aquarium. (The density of water is 1000 kg/m3.)
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In a similar example in the book, they do the problem the same way, but they just throw the units in at the end, after they've computed the answer. I could do the same on this homework problem and get full credit, but I just got to know... :smile:


 
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  • #2
What makes you think that unit is wrong? What's the definition of work?
 
  • #3
oops... It's getting late. I don't know why I was expecting Newtons. Thanks!
 

1. What is a work problem?

A work problem is any scenario that involves calculating the amount of work done by a force on an object. This can include problems involving force, distance, and/or time.

2. What are the common units used in work problems?

The most common units used in work problems include joules (J) for work, newtons (N) for force, meters (m) for distance, and seconds (s) for time. It is important to use the correct units in calculations to ensure accurate results.

3. Why is it important to use the correct units in work problems?

Using the correct units in work problems is important because different units represent different quantities and using the wrong units can lead to incorrect calculations and results. It is also important for consistency and clarity in communicating scientific information.

4. What should I do if I get the right answer, but with the wrong units in a work problem?

If you get the right answer, but with the wrong units in a work problem, you should convert the units to the correct ones. This can be done by using conversion factors or dimensional analysis to ensure accuracy in your calculations.

5. How can I avoid using the wrong units in a work problem?

To avoid using the wrong units in a work problem, it is important to carefully read the problem and identify the given and required units. Also, double-check your calculations and make sure all units are consistent throughout the problem. It can also be helpful to practice unit conversions and familiarize yourself with common units used in work problems.

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