In a cathode ray tube, electrons initially at rest are accelerated by a uniform electric field of magnitude 4.71 x 105 N/C during the first 5.49 cm of the tube's length; then they move at essentially constant velocity another 47.9 cm before hitting the screen. Find the speed of the electrons when they hit the screen

Question

In a cathode ray tube, electrons initially at rest are accelerated by a uniform electric field of magnitude 4.71 x 105 N/C during the first 5.49 cm of the tube's length; then they move at essentially constant velocity another 47.9 cm before hitting the screen. Find the speed of the electrons when they hit the screen
How long does it take them to travel the length of the tube?

bobpursley · Answer

1/2 m v^2= Eqd solve for v. then, find the time to move .05 (d) at V/2 (avg velocity during acceleration), and the time to move .479 at V. add the times.