JEE MAIN - Physics (2003 - No. 14)
A particle of mass $$M$$ and charge $$Q$$ moving with velocity $$\overrightarrow v $$ describe a circular path of radius $$R$$ when subjected to a uniform transverse magnetic field of induction $$B.$$ The network done by the field when the particle completes one full circle is
$$\left( {{{M{v^2}} \over R}} \right)2\pi R$$
zero
$$B\,\,Q\,2\pi R$$
$$B\,Qv\,2\pi R$$
Explicació
The work done, $$dW = Fds\,\cos \,\theta $$
The angle between force and displacement is $${90^ \circ }.$$
Therefore work done is zero.
The angle between force and displacement is $${90^ \circ }.$$
Therefore work done is zero.