Question

0:9
20. An electron moves along +x direction. It enters into a region of uniform
magnetic field B directed along -z direction as shown in fig. Draw the
shape of trajectory followed by the electron after entering the field.​

Answer 1

So, first of all, understand the question.

There's an electron (-ve) moving towards +x axis with some velocity and there's magnetic filed towards the -z axis, hence using right hand rule, we can conclude that, the trajectory of electron will shift towards -y axis, as it's a negative charge.