Two point charges, +Q and -Q, are placed at a distance d apart. What is the electric potential at the midpoint between them?
Practice Questions
1 question
Q1
Two point charges, +Q and -Q, are placed at a distance d apart. What is the electric potential at the midpoint between them?
0
kQ/d
kQ/2d
kQ/4d
At the midpoint, the potentials due to both charges cancel each other out, resulting in a net potential of 0 V.
Questions & Step-by-step Solutions
1 item
Q
Q: Two point charges, +Q and -Q, are placed at a distance d apart. What is the electric potential at the midpoint between them?
Solution: At the midpoint, the potentials due to both charges cancel each other out, resulting in a net potential of 0 V.
Steps: 8
Step 1: Identify the two point charges: one is +Q (positive) and the other is -Q (negative).
Step 2: Determine the distance between the two charges, which is given as d.
Step 3: Find the midpoint between the two charges. This point is located at a distance of d/2 from each charge.
Step 4: Calculate the electric potential due to the positive charge (+Q) at the midpoint. The formula for electric potential (V) is V = k * Q / r, where k is a constant, Q is the charge, and r is the distance from the charge.
Step 5: For the positive charge, the potential at the midpoint is V+ = k * Q / (d/2) = 2kQ/d.
Step 6: Calculate the electric potential due to the negative charge (-Q) at the midpoint using the same formula. The potential is V- = k * (-Q) / (d/2) = -2kQ/d.
Step 7: Add the potentials from both charges at the midpoint: V_total = V+ + V- = (2kQ/d) + (-2kQ/d).
Step 8: Simplify the total potential: V_total = 0.
