Question

An electron is moving in a circular orbit in a uniform magnetic field. Is the kinetic energy of the electron changing?

Answer 1

kinetic energy does not change

Step-by-step explanation:

you can use the formula for the kinetic energy of the electron and for the radius of the trajectory of an electron in a uniform magnetic field:

`E_k=(1)/(2)m_ev^2\\\\r=(m_e v)/(qB)`

me: mass of the electron

B: magnetic field

q: charge of the electron

r: radius

By doing v the subject of the formula and replace it in the expression for the kinetic energy you obtain:

`v=(rqB)/(m_e)\\\\E_k=(1)/(2)m_e((rqB)/(m_e))^2=(r^2q^2B^2)/(2m_e)`

as youcan see, all parameters r, q, B and me are constant.

hence, the kinetic energy does not change