What does the velocity equation prove?

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SUMMARY

The equation v² = 2E_k/m illustrates the relationship between velocity, kinetic energy, and mass, rather than proving direct proportionality. It is more accurate to state that, given constant kinetic energy, velocity is inversely proportional to the square root of mass, though this is a complex assertion. The more straightforward interpretation is that kinetic energy is proportional to both mass and the square of velocity. Additionally, the discussion touches on how Newtonian mechanics relates to the time experienced by a freely falling object, influenced by gravitational acceleration and initial velocity.

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  • Understanding of kinetic energy and its formula E_k = 1/2 mv²
  • Familiarity with Newtonian mechanics and its principles
  • Basic knowledge of algebraic manipulation of equations
  • Concept of proportional relationships in physics
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  • Research the implications of kinetic energy in different physical scenarios
  • Study the relationship between mass, velocity, and kinetic energy in various contexts
  • Explore the principles of Newtonian mechanics in detail
  • Investigate the mathematical derivation of motion equations under constant acceleration
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Does this equation v^2= \frac {2E_k} {m} prove that the velocity is inversely proportional to the mass of the object?
 
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That equation doesn't "prove" anything. Equations don't "prove" things, they just give you relations between things. That equation gives you the relationship between the velocity, the kinetic energy, and the mass. Usually the equation is written like so: $$E_k=\frac{1}{2}mv^2$$ to emphasize that this equation tells you what the kinetic energy is, given the velocity. The higher the velocity, the higher the kinetic energy. A statement like "velocity is inversely proportional to the mass of the an object" is not a useful statement. At the very least you would have to specify that "given the kinetic energy is constant, the velocity is inversely proportional to the square-root of the mass". Although true, that statement is too convoluted to give much physical insight. A much more useful statement would be "the kinetic energy of an object is proportional to the object's mass and to its velocity squared."
 
Well, I can have v=-gt+v_0 \Rightarrow t=\frac{v_0-v}{g}. Does it mean that Newtonian mechanics predicts how a freely falling object experiences time, depends on the acceleration of gravity of that place and its initial velocity?
 

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