Matrix operations in a general physics problem

AI Thread Summary
The discussion focuses on a physics problem involving a lemming falling from an iceberg, requiring matrix operations to analyze the fall. Participants explore how to represent the fall mathematically using time and altitude data, while also addressing how to calculate the time of impact with the ocean and the lemming's speed upon opening an umbrella. The conversation highlights the need for proper matrix setup to derive equations for acceleration and velocity, emphasizing the importance of the second time-derivative of displacement. There is some confusion regarding the correct application of matrix operations and the structure of the problem. Overall, the thread seeks to clarify the mathematical approach to solving the given physics scenario.
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Homework Statement



A lemming marches off an ice berg, falling directly downward from a height of 12.40 meters. 0.10 seconds later, he is 9.151 meters above the ocean below. 0.20 seconds this altitude is reduced to 5.804 meters, and at 0.30 seconds he as fallen to 2.359 meters above the ocean.


1. Via Matrix operations, develop a mathematical expression that represents this fall.
2. If the lemming failed to bring an umbrella, how many seconds into this fall would he impact the ocean?
3. If he did have an umbrella to break his fall, and he opened it 7.000 meters above the water, how much time would he have fallen freely prior to opening the umbrella?
4. What would his speed be the instant he opened his umbrella?
5. What is his acceleration due to gravity?

_______________________________

I know the Times (t) and the altitudes (a)
I know there is an I, J, and K component when dealing with velocity and such in physics.


Homework Equations



-Sarrs Law could be used to solve a 3x3 or 2x2 matrix, however, I don't think that is possible for this particular problem.

To find the acceleration, I know to take the f''(x) is required.

The Attempt at a Solution



0, 0.10, 0.20. 0.30 (T)
12.40, 9.151, 5.804, 2.359 (A)

If I new this was right and how to solve this thing, I think I could take the determinant to get part B?

For part C, I think I could plug in the 7.000 into my velocity equation.



Again, without the matrix, I can not derive the first equation.
This is a high school physics problem.
 
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To find the acceleration, I know to take the f''(x) is required.
You mean you take ##\ddot{f}(t)## ? Acceleration requires the second time-derivative of displacement.

What is the matrix for the second derivative operation?

However - you want to be able to predict the future positions and speeds.
The trick with this would be setting up the correct vectors.

I know the Times (t) and the altitudes (a)
I know there is an I, J, and K component when dealing with velocity and such in physics.
Well - the lemming is going just downwards so you can get rid of two of the components.

... to get part B? ... For part C
There is no part B or C in your problem as you've written it.
 
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