An electron is traveling in a straight line heading East through a region with a uniform electric field of 3 N/C directed upwards. In the region there is also a uniform magnetic field with a strength of 2 T.

An electron is traveling in a straight line heading East through a region with a uniform electric field of 3 N/C directed upwards. In the region there is also a uniform magnetic field with a strength of 2 T.

(a) What must be the direction of the B-field? Explain your reasoning. (3 Marks)

(b) What is the speed of the electron? (2 Marks)

(c) If a proton were sent in to this region (with the same speed) what would be different about its motion compared to the electron’s motion? Explain. (2 Marks)

(d) The electric field is suddenly turned off. With what radius do the proton and electron move in circles inside the B-field region? (4 Marks)