Open Question
An aluminum wire consists of the three segments shown in FIGURE P27.64. The current in the top segment is 10 A. For each of these three segments, find theb. Current density J. Place your results in a table for easy viewing.
27. Resistors & DC Circuits
Intro to Current
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A wire is connected to the positive and negative plates of a capacitor. Electrons in the wire feel an attraction toward the positive plate of a capacitor, and a repulsion from the negative plate. What is true about the motion of these electrons?
A
The electrons' speeds increase the entire time the capacitor is connected.
B
The electrons' speeds decrease the entire time the capacitor is connected.
C
Electrons are not the particles that are moving.
D
There is not enough information to answer.
E
The electrons keep speeding up, then colliding with other particles, and then repeating.
Verified step by step guidance1
Understand the setup: A capacitor consists of two plates, one positively charged and one negatively charged. When a wire is connected, electrons in the wire are influenced by the electric field created by the charges on the plates.
Identify the forces on the electrons: Electrons are negatively charged particles. They are attracted to the positive plate and repelled by the negative plate due to the electric field between the plates.
Consider the motion of electrons: As electrons move towards the positive plate, they accelerate due to the electric field. This means their speed increases as they move through the wire.
Account for collisions: In a real wire, electrons do not move freely without interruption. They frequently collide with atoms in the wire, which temporarily slows them down before they accelerate again due to the electric field.
Conclude the behavior: The electrons' motion is characterized by a cycle of speeding up due to the electric field and then slowing down due to collisions, resulting in an overall zigzag path as they move through the wire.
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