- #1

TheCelt

- 24

- 5

- Homework Statement
- Relate energy equation to the momentum equation for particles

- Relevant Equations
- $$\lambda = h/p$$

$$p = mv$$

$$E=1/2mv^2$$

I am trying to relate these equations to get the energy with respect to momentum based on particle wavelengths.

I did the following:

$$\lambda = h/p$$ so $$p= h/ \lambda $$

Then

$$p=mv$$ and $$E=1/2mv^2$$

So

$$E = pv/2 $$

But the answer was:

$$E = p^2/2m $$

I don't understand how they got this answer or why mine is wrong ?

I did the following:

$$\lambda = h/p$$ so $$p= h/ \lambda $$

Then

$$p=mv$$ and $$E=1/2mv^2$$

So

$$E = pv/2 $$

But the answer was:

$$E = p^2/2m $$

I don't understand how they got this answer or why mine is wrong ?