What does the velocity equation prove?

In summary, the equation v^2= \frac {2E_k} {m} shows the relationship between velocity, kinetic energy, and mass. It does not prove anything, but rather provides a useful relationship. When written as E_k=\frac{1}{2}mv^2, it tells us the kinetic energy given the velocity. The statement "velocity is inversely proportional to the mass of an object" is not very informative and a more useful statement would be "the kinetic energy is proportional to the mass and velocity squared." Additionally, the equation v=-gt+v_0 \Rightarrow t=\frac{v_0-v}{g} can be used to predict how a freely falling object experiences time based on the acceleration of
  • #1
avito009
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Does this equation [tex] v^2= \frac {2E_k} {m} [/tex] prove that the velocity is inversely proportional to the mass of the object?
 
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  • #2
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."
 
  • #3
Well, I can have [itex] v=-gt+v_0 \Rightarrow t=\frac{v_0-v}{g} [/itex]. 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?
 

1. What is the velocity equation?

The velocity equation, also known as the average velocity equation, is a mathematical formula that calculates the average speed of an object over a certain time period. It is typically represented as v = d/t, where v is velocity, d is distance, and t is time.

2. How is the velocity equation derived?

The velocity equation is derived from the fundamental principles of physics, specifically the concept of displacement and time. It is derived by dividing the total distance traveled by an object by the total time taken, resulting in the average speed or velocity of the object.

3. What does the velocity equation prove about an object's motion?

The velocity equation proves that an object's motion is directly related to its displacement and time. It shows that as an object's displacement increases, its velocity also increases, and as the time taken for the object to travel increases, its velocity decreases.

4. What are some real-world applications of the velocity equation?

The velocity equation has many real-world applications, including sports analytics, traffic engineering, and transportation planning. It is also used in physics and engineering to study the motion of objects and to design machines and structures that are dependent on velocity.

5. Can the velocity equation be used to calculate instantaneous velocity?

No, the velocity equation can only calculate average velocity over a certain time period. To calculate instantaneous velocity, a different formula is used, which involves taking the derivative of the displacement function with respect to time.

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