This topic contains a solution. Click here to go to the answer
« previous next »

Author Question: A plastic hose stuffed more or less densely with steel wool and a source of water can act as a model ... (Read 72 times)

BrownTown3

  • Hero Member
  • *****
  • Posts: 564
on: Jul 28, 2018
A plastic hose stuffed more or less densely with steel wool and a source of water can act as a model for resistance and electric current in wires. Suppose two one-meter lengths of such a hose were stuffed identically with steel wool.
 
  Discuss how one could use this model to determine which of the following would have greater resistance: one length; two lengths connected one after another; two lengths connected side by side, both connected to one source of water. Speculate on the answers as best you are able.

Question 2

Why is the wire connecting your dryer to the circuit breaker in your house thicker (of greater diameter) than the wire connecting a table lamp to the electric outlet?
 
  What will be an ideal response?


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

soda0602

  • Sr. Member
  • ****
  • Posts: 313
Reply #1 on: Jul 28, 2018
Answer to Question 1

This exploits the model discussed above for resistance. The single lengths of hose
have the same resistivitycaused by the steel wool stuffing. Connect two hoses in series
(one after another) and the resistance increases. Connect two hoses side by side (assume
that it is possible to do so without leaks occurring), and the water has more ways to get
through to the other sidethere is less resistance. Two lengths side by side has the least
resistance of the choices offered; two one after the other has the most resistance. In fact, by
our argument, the two side by side have half the resistance of the single length, and the two
one after another have twice the resistance of the single length.

Answer to Question 2

In the book, we mention the resistivity as the basis of resistance. For a given
diameter, both pieces of wire would have the same resistivity but a longer piece will have a
greater resistance. Here, both pieces of wire would have the same resistivity but their
diameters would be different. This difference gives rise to the difference in resistance. The
thinner wire exhibits greater resistance than thicker wire. This occurs because the larger wire
allows the charges more space to get by the atoms on the lattice (this way of thinking
about currents reflects the classical Drude model of conductivity). The thicker wire can
therefore carry much more current without generating too much Joule heat.


BrownTown3

  • Member
  • Posts: 564
Reply 2 on: Jul 28, 2018
Great answer, keep it coming :)

blakcmamba

  • Member
  • Posts: 335
Reply 3 on: Yesterday
Gracias!

« previous next »
 

Did you know?

A headache when you wake up in the morning is indicative of sinusitis. Other symptoms of sinusitis can include fever, weakness, tiredness, a cough that may be more severe at night, and a runny nose or nasal congestion.

Did you know?

Cutaneous mucormycosis is a rare fungal infection that has been fatal in at least 29% of cases, and in as many as 83% of cases, depending on the patient's health prior to infection. It has occurred often after natural disasters such as tornados, and early treatment is essential.

Did you know?

The use of salicylates dates back 2,500 years to Hippocrates's recommendation of willow bark (from which a salicylate is derived) as an aid to the pains of childbirth. However, overdosage of salicylates can harm body fluids, electrolytes, the CNS, the GI tract, the ears, the lungs, the blood, the liver, and the kidneys and cause coma or death.

Did you know?

Anesthesia awareness is a potentially disturbing adverse effect wherein patients who have been paralyzed with muscle relaxants may awaken. They may be aware of their surroundings but unable to communicate or move. Neurologic monitoring equipment that helps to more closely check the patient's anesthesia stages is now available to avoid the occurrence of anesthesia awareness.

Did you know?

Each year in the United States, there are approximately six million pregnancies. This means that at any one time, about 4% of women in the United States are pregnant.

Model Organism Neurospora Model Organism Neurospora
Human Heart Model Human Heart Model
A single overhead camshaft engine with a timing belt that also rotates the water pump. A single overhead camshaft engine with a timing belt that also rotates the water pump.
Water Vapor and Liquid Water Water Vapor and Liquid Water
Water transport in plants Water transport in plants
Water as a Polar Molecule Water as a Polar Molecule
Video: Leukemia

For a complete list of videos, visit our video library