What is the magnitude and direction of the acceleration on the electron in a 3T magnetic field ( -k) and an 800 V/m (-j) electric field, shown below (neglecting gravity), if its velocity is 300 m/s? X X X B= 3.0 T X X -e X X X X X X E=800 V/m

13. You have decided to use a magnetic field in combination with an electric field as a switch to either make a beam of electrons pass straight through a certain region of an apparatus or to curve 90° and go through an auxiliary portion of the apparatus. The beam of electrons travels to the right at a speed of 4.8 x 106 m/s and you designed the electric field (8400 V/m) to be oriented 10⁰ vertically up. a) When the electric field is on, what strength of B-field is necessary for the beam to travel un-deflected? (Note: You can ignore gravity.) b) What is the orientation of the B-field? c) When the electric field is turned off, how long does it take an electron to turn into the auxiliary apparatus?

(a) A velocity selector consists of electric and magnetic fields described by the expressions E = Ek and B = Bj, with B = 24.0 mT. Find the value of E (in kV/m) such that a 780 eV electron moving in the negative x-direction is undeflected. 3.97e24 How do you determine the speed of the electron if you know its kinetic energy? kV/m (b) What If? For the value of E found in part (a), what would the kinetic energy of a proton have to be (in MeV) for it to move undeflected in the negative x-direction? MeV

An electric field with initial magnitude 210 V/m directed into the page and increasing at a rate of 13.0 V/(ms) is confined to the area of radius R = 15.0 cm in the figure below. If r = 45.0 cm, what are the magnitude and direction of the magnetic field at point A? magnitude direction ---Select--- Ø Ø A O R