Recent content by debis

ah yes, i got it. i was so caught up in the diff eq part of it i forgot about simple vecor analysis. i always make things more complicated than they are :/ thank you so much everyone for your help, particularly qbert, your hint really helped :)

i tried to find \frac{d}{dt}\left\vert\frac{d\vec{r}}{dt}\right\vert but i don't know how to handle a diff eq with a vector product in it - i understand in theory how proving all the above mentioned things would work, my main question was how to handle a cross product in a differential...

it just says arbitrary, so I'm assuming it means it could be variable or constant (it's definitely not reliably constant because the next question is "assuming the field is a constant") i tried using circular motion with it for the constant speed, but i didn't understand how to apply it...

Vector Product Differential Equation If a particle with charge e and mass m is in an arbitrary magnetic field has motion described by: m\frac{d^2\vec{r}}{dt^2}=\frac{e}{c}\frac{d\vec{r} }{dt}\times\vec{H} prove that the speed v\equiv\left\vert\frac{d\vec{r}}{dt}\right\vert is constant. I...

If a particle with charge e and mass m is in an arbitrary magnetic field has motion described by: m\frac{d^2\vec{r}}{dt^2}=\frac{e}{c}\frac{d\vec{r}}{dt}\times\vec{H} prove that the speed v\equiv\left\vert\frac{d\vec{r}}{dt}\right\vert is constant. I don't understand how to do this...