Best straightforward method to calculate the direction of the Lorentz force

[greg_rack]

Hi guys, I'm being introduced to magnetism, and the direction of the Lorentz force is quite confusing since it's involving a vector product.
Which method would you recommend me in order to easily deduce the direction?

 

[Dale]

Can you write which formula you are having trouble with?

 

[A.T.]

.. it's involving a vector product.
Which method would you recommend me in order to easily deduce the direction?

From: https://en.wikipedia.org/wiki/Cross_product#Definition

But note that for negative charges the direction flips, so you can use the left hand.

 

[greg_rack]

From: https://en.wikipedia.org/wiki/Cross_product#Definition

But note that for negative charges the direction flips, so you can use the left hand.

That's what I meant, thank you very much!

 

[PeroK]

That's what I meant, thank you very much!

Alternatively, imagine the usual $x-y$ axes, with the x-axis pointing left to right across the page and the y-axis pointing up the page, then the z-axis is upwards from the page. And $\vec x \times \vec y = \vec z$.

 

[A.T.]

That's what I meant, thank you very much!

Note that you can cycle the fingers used. I personally find this easier to remember:

thumb X index-finger = middle-finger

because it is the finger order I use in counting.