Check for me this solution in General Physic

In summary, the conservation of linear momentum only applies to objects with a total net force of zero. In cases where gravity is still present, the total net force is mg. The solution is correct and the impulse momentum theorem can be used to calculate the average external force, change in time, initial and final momentum. However, in real life situations, there may be additional factors to consider such as air drag and variation in g and atmospheric pressure.
  • #1
vuvan
4
0

Homework Statement



I reckon that we only apply conservation of linear momentum for object which has total net force acting on equal zero but in this case , the gravity force still exist , total net force is mg
Thank in advance




Homework Equations





The Attempt at a Solution

 

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  • #2
So i reckon the solution is wrong ? how do you think
 
  • #3
No the solution is right.
By impulse momentum theorem: Favg.ext Δt + mu = mv

Since the time span of the explosion and by inference your observation is very short and gravity forces are comparatively weak,the change in net momentum of the system is very very small and hence momentum is conserved in a meaningful way.You can dispute that but thinking that physics in real life is full of approximations(you are ignoring air drag,variation of g and atmospheric pressure with altitude etc. already), it should seem reasonable.However the same is not true when the external force is impulsive or the time span of observation is big enough.
 

1. What is the purpose of checking a solution in General Physics?

The purpose of checking a solution in General Physics is to ensure that the solution is correct and accurate. This helps to verify the understanding of the concepts being applied and can identify any errors that may have been made during the problem-solving process.

2. How do I check a solution in General Physics?

To check a solution in General Physics, you should follow the steps outlined in your textbook or by your instructor. This typically involves plugging the solution back into the original equation and verifying that it satisfies all given conditions and equations.

3. What should I do if my solution does not match the expected answer?

If your solution does not match the expected answer, you should go back and review your work to identify any mistakes that may have been made. It is also helpful to check your units and make sure they are consistent with the expected units for the answer.

4. Can I use a calculator to check my solution in General Physics?

Yes, you can use a calculator to check your solution in General Physics. However, it is important to make sure you are entering the correct values and using the appropriate functions on your calculator. Additionally, be sure to round your answer to the appropriate number of significant figures.

5. Are there any tips for checking a solution in General Physics?

Yes, there are a few tips for checking a solution in General Physics. These include checking your units for consistency, double-checking your calculations, and plugging your solution into the original equation to verify it satisfies all given conditions. It can also be helpful to compare your answer to the expected answer and identify any potential errors.

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