Please explain how to do this. I know Vab= 40V because of the potential differen
ID: 1568400 • Letter: P
Question
Please explain how to do this.I know Vab= 40V because of the potential difference being either +/- 20 V. It has to be minus because after being released from rest, the proton goes toward another charge. It would have to be a negative charge for it to go there so potential decreases. I don't understand the eV and the other parts of the question. Please help. 2. When released from rest at point A, a proton flies to point B. The potential at point A is 60 V. The potential difference between pointsA and Bis 20v (plus or minus). (30 points) A. What is the potential at point B? Explain. B. What is the change in potential energy in Joules as the proton in goes from A to B? Is this an increase or decrease in potential energy? -C. What is the change in potential energy in ev? D. What is the external work done as the proton goes from A to B? E. what is the change in the proton's kinetic energy in ev in going from A to B?
Explanation / Answer
Assuming the Electric field is due to an Electron( Negative charge), we can infer that the Point B is closer to the Electron that Point A as the Proton flies from A to B .
Hence, B is at a higher Potential than A.
Potential at A, VA= 60V
Since Potential Difference btwn A and B is 20V, it implies that VB will be 80V as we know that B is at a higher Potential.
a) Potential at B, VB= 80V
b) Change in Potential energy = VAB * Charge = 20V * 1.6 * 10-19C = 32 * 10-19J
This is a decrease in Potential Energy as the Proton has moved from Lower Potential to Higher Potential.
c) Change of PE in eV = (20V) * (Charge on 1 Electron) = - 20eV
d) External work Done = 0, since the Proton has gained whatever Potential Energy it has lost in the form of Kinetic Energy.
e) Change in Proton's KE in going from A to B = Loss in PE in eV = + 20 eV