A very long uniform line of charge, has a charge per unit length lambda = -1.50
ID: 1413099 • Letter: A
Question
A very long uniform line of charge, has a charge per unit length lambda = -1.50 nC and lies along the z-axis. A point charge q =3.00 nC is located on the y-axis at y = 2.50 m. Find the net electric field at a point A, with coordinates x=2.00 m, y =1.50 m, z =0.00 m (use I - hat, J - hat, k - hat notation). Find the electric potential difference V_BA = V_B -V_A. between point B (with coordinates x = 0.00 m, y =1.50 m, R=0.00 m) and point A. A proton (m_p= 1.67 times 10^-27 kg q_p = 1.60 times 10^-19 C) travels from point A to point B. Its speed at point A is V_A = 1.50 times 10^4m/s. What is its speed at point B?Explanation / Answer
a) Net electric field = 2 * 8.98 * 109 * 1.50 * 10-9/2.5 - 8.98 * 109 * 3 * 10-9/5
= 5.388 N/C
b) Electric potential difference = 8.98 * 109 * 3 * 10-9 * (1/2.236 - 1/2.5)
= 1.272 V
c) total energy = 1.6 * 10-19 * 1.272
= 2.0352 * 10-19 J
=> speed at point B = sqrt(3.914 * 10-19 * 2/1.67 * 10-27)
= 2.165 * 104 m/sec