Law Conservation of Energy: Starting off a solution for 11b

In summary, the conversation discusses solving a problem involving the Law of Conservation of Energy and the use of equations such as ΔEsystem + ΔEsurroundings =0 and ΔEsystem = ΔU + ΔEk + ΔEp. There is also a mention of finding the system boundary and the heat generated by friction within or outside of this boundary.
  • #1
Jigga
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0

Homework Statement


upload_2018-6-9_17-43-24.png


Homework Equations


ΔEsystem + ΔEsurroundings =0

The Attempt at a Solution


I have solved 11a and got 5m/s.
I can do 11b just by just jumping to Ek = Fs (from the work kinetic energy theorem), but I would like to do it formally from first principles using the Law of Conservation of Energy.
I would then like to make use of
ΔEsystem + ΔEsurroundings =0
and then make use of ΔEsystem = ΔU + ΔEk + ΔEp
and then make use of ΔU = W + Q
and then introduce W = Fs
then solve for F.
However I am not sure where to put the system boundary so this is solvable. Then the question of the pluses and minuses.


Many thanks
 

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  • #2
Depending on where you draw the system boundary the heat generated by friction will either remain within the system boundary (part of Delta E system) or cross the boundary (part of Delta E Surroundings) either way it's solvable.
 
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1. What is the Law of Conservation of Energy?

The Law of Conservation of Energy states that energy cannot be created or destroyed, it can only be transformed from one form to another. This means that the total amount of energy in a closed system remains constant over time.

2. How does the Law of Conservation of Energy apply in everyday life?

The Law of Conservation of Energy can be seen in many everyday activities, such as turning on a light switch. The electrical energy is transformed into light and heat energy. It also applies to more complex systems, such as the human body, where the food we eat is converted into energy for our bodies to use.

3. Can the Law of Conservation of Energy be violated?

No, the Law of Conservation of Energy is a fundamental law of physics and has been proven to hold true in every observed physical process. It is a fundamental principle in understanding the behavior of energy in the universe.

4. What is the role of energy conservation in environmental sustainability?

Energy conservation plays a crucial role in environmental sustainability by reducing the amount of energy we use, which in turn reduces our impact on the environment. By following the Law of Conservation of Energy, we can ensure that we are not depleting our natural resources and contributing to climate change.

5. How can we apply the Law of Conservation of Energy in solving problems?

The Law of Conservation of Energy can be applied in problem-solving by using it as a tool to analyze and predict the behavior of energy in a system. By understanding how energy is transferred and transformed, we can identify the key factors and variables in a problem and come up with a solution that conserves energy.

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