Linear Momentum Algebraic interpretation

AI Thread Summary
A light object and a heavy object can have the same kinetic energy, but their momenta differ due to their mass and velocity relationship. The discussion emphasizes using algebra to derive the relationship between kinetic energy and momentum, suggesting a different approach by expressing velocity in terms of momentum. The key relationship involves the ratio of kinetic energies being proportional to the squares of their momenta. This algebraic interpretation helps clarify that the heavier object will have greater momentum despite having the same kinetic energy as the lighter object. Understanding this relationship is crucial for solving the problem effectively.
brycenrg
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Homework Statement


A light object and a heavy object have the same kinetic energy. Which has more momentum?

Homework Equations


I am trying to prove this through algebra.
I don't understand how to show this any help?

The Attempt at a Solution


1/2m1v1^2 = 1/2m2v2^2 when m1 > m2

v1 = v2 squareroot(m2/m1)

m1v2 squareroot(m2/m1) = m2v1 squareroot(m1/m2)
 
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brycenrg said:

Homework Statement


A light object and a heavy object have the same kinetic energy. Which has more momentum?

Homework Equations


I am trying to prove this through algebra.
I don't understand how to show this any help?

The Attempt at a Solution


1/2m1v1^2 = 1/2m2v2^2 when m1 > m2

v1 = v2 squareroot(m2/m1)

m1v2 squareroot(m2/m1) = m2v1 squareroot(m1/m2)

I do not see what is the sense of your last line. What are the momenta?
 
I suggest you work in the other direction and do not use v as a variable. Instead, solve for v from p = mv and insert this into the expression for kinetic energy.
 
Here's a hint. You do have to use algebra here, but this is only a qualitative question where you have to find the relationship

## \frac{KE_1}{KE_2} = constant = \alpha(m_1, m_2) \frac{p_1^2}{p_2^2} ##

where ## \alpha ## is a function of the two masses. Once you find this relationship, you can answer the question easily.

Goodluck! ;)
 
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