Deriving the Equation v^2 = u^2 + 2as

[Marcsmeets]

Homework Statement

Derive the equation v^2 = u^2 + 2as

I have no clue how to do this please can someone help!

Thank you!

 

[barryj]

Notice that there is no t involved in this relationship. Look at your equations for distance and average acceleration and see how to eliminate t.

 

[gneill]

I don't know about you, but whenever I see velocity-squared terms I tend to think about kinetic energy...

 

[barryj]

gneill, I am sure you are correct but you can also derive this equation from two basic equations and energy principals are not required.

 

[gneill]

gneill, I am sure you are correct but you can also derive this equation from two basic equations and energy principals are not required.

Sure. But it's nice to have options. Some approaches are more intuitively obvious to different people.

 

[barryj]

If you use energy, then you have to introduce mass and this is not necessary.

 

[gneill]

If you use energy, then you have to introduce mass and this is not necessary.

Mass disappears by cancellation. No biggie. Or use specific energy

 

[barryj]

So why complicate a simple problem?

 

[gneill]

So why complicate a simple problem?

It's no more complicated an approach if you're familiar with the concept. Like I said, different strokes for different folks.

Let's wait to see what the OP comes up with.

 

[IamBatman]

Derive via using other kinematic equations?

 

[Mandelbroth]

Homework Statement

Derive the equation v^2 = u^2 + 2as

I have no clue how to do this please can someone help!

Thank you!

Note that this equation is assuming that acceleration, the derivative of velocity with respect to time, is constant. This is, then, just a simple exercise in calculus.

 

[Chestermiller]

Hi Marksmeets. Welcome to Physics Forums. We can best answer your question if we know whether you have had calculus yet. Have you?

 

[IamBatman]

I'm thinking if its an intro class then there's no calculus and just want you to use other kinematic equations to this one. I remember having a question where it was just that for intro physics but I can't be certain about op.

 

[barryj]

This is definitely an intro physics question. Only algebra 1 is needed, that is if you have the two kinematic equations.