In graph theory, a planar graph is a graph that can be embedded in the plane, i.e., it can be drawn on the plane in such a way that its edges intersect only at their endpoints. In other words, it can be drawn in such a way that no edges cross each other. Such a drawing is called a plane graph or planar embedding of the graph. A plane graph can be defined as a planar graph with a mapping from every node to a point on a plane, and from every edge to a plane curve on that plane, such that the extreme points of each curve are the points mapped from its end nodes, and all curves are disjoint except on their extreme points.
Every graph that can be drawn on a plane can be drawn on the sphere as well, and vice versa, by means of stereographic projection.
Plane graphs can be encoded by combinatorial maps or rotation systems.
An equivalence class of topologically equivalent drawings on the sphere, usually with additional assumptions such as the absence of isthmuses, is called a planar map. Although a plane graph has an external or unbounded face, none of the faces of a planar map has a particular status.
Planar graphs generalize to graphs drawable on a surface of a given genus. In this terminology, planar graphs have genus 0, since the plane (and the sphere) are surfaces of genus 0. See "graph embedding" for other related topics.
Homework Statement
The question is in regards to a homework problem, but I only need clarification on how to interpret the graph of a waveform.
Homework Equations
N.A.
The Attempt at a Solution
N.A.
I've attached the image. I am assuming that one cycle of the waveform takes...
Hey all,
Wanting to create an up/down counter that uses a photogate as a trigger, and a 12 segment LED bar graph to display the count. It will need to begin at full illumination, turning off one at a time on activation of the photogate. Will also need a reset switch, though I'm thinking a...
Homework Statement
A firework rocket is fired vertically upwards from the ground. It accelerates uniformly from rest with an acceleration of 8.0 ms−2 for 5.0 s after which time the fuel of the rocket has all been used. Sketch graphs to show how the gravitational potential energy and the...
Homework Statement
I have to calculate the displacements from a velocity-time graph to make a position-time graph.
The velocity-time graph from the question is attached.
Homework Equations
d=vtThe Attempt at a Solution
To calculate the values for a position-time graph, I first converted all...
Homework Statement
Homework Equations
ΔU = -q∫E * ds
The Attempt at a Solution
Just by looking at the graph I am thinking, if I solve for E using the equation above, the number would be always negative therefore I can conclude that the electric field at any x position would be negative and...
Homework Statement
Prove that every graph G without isolated vertices has a matching of size at least n(G)/(1+∆(G)). (Hint: Apply induction on e(G)).
Homework Equations
n(G) = size of the vertex set of G and ∆(G)= maximum degree of v in G
The Attempt at a Solution
For the base...
A train starts from rest from a station and travels with uniform acceleration 0.5m/s^2 for 20s. it travels with uniform velocity for another 30s, the brakes are then applied so that a uniform retardation is obtained and the train comes to rest in a further 10s. sketch the velocity-time graph of...
Hello,
I have a graph of a tensile test of a metal sample, and I wish to find the slope on the graph of only the elastic region of the graph, meaning of the entire graph, there is only one section of it that I am interested in finding the slope for.
Is there a way in excel to make it such...
Homework Statement
when graphing a velocity squared vs. time graph how do I find the acceleration. I realize the slope gives me units of acceleration but this is not correct because the theoretical acceleration is no where near this and I didnt botch this lab up.
Theoretical
a =...
Homework Statement
Prove that if a graph has > (n-1)(n-2) /2 edges, it is connected.
Homework Equations
??
The Attempt at a Solution
I've drawn several examples and made tables, and I can see that the graph is indeed connected if it has more edges than [(n-1)(n-2)]/2. But...
Homework Statement
The graph of acceleration versus time for an object in linear motion. Assuming the object starts from rest at the origin at t = 0, find the velocity and position of the object at times t = 1 through 10 seconds.
Homework Equations
##v=v_i + at##The Attempt at a Solution
I...
Hi All,
I am contemplating which graph theory text to purchase. I am stuck between
a) Graph Theory by Bondy and Murty
B) Graph Theory by Richard Diestel
I have already been through Trudeau's intro text on my own and am looking for something deeper and more advanced. I am...
For example vertice A connected to vertice B and vertice C connected to vertice D? Would this be considered two different graphs? Here is a graph, would it be bipartite?
Homework Statement
The graph below shows the vertical displacement of an object as a function of time.
(a) Construct a graph of the object’s velocity as a function of time.
(b) Construct a graph of the object’s acceleration as a function of time.
(c) Describe a scenario in which a...
Homework Statement
What could be the reason why the graph is formed the way it is?Homework Equations
τ = 2π(L/g)^(1/2)
The Attempt at a Solution
I don't know how to explain it. Anyone know why one is a linear and another is a curve?
My physics problem ask me to find the average acceleration on a velocity time graph. On the graph, velocity is at -6 constantly from 0 - 5 s.
I know that an question to use would be average accerlation = delta v/ delta t
The problem is I did that and I still got it incorrect on...
We are given a velocity vs. time graph. It starts at 15 m/s at t=0 and goes to -10m/s at t=4
then it goes from -10m/s at t=4 to 15m/s at t=10 and we are told to find the postion after t=10
I first found the slope of the first segment which was -6.25. so I did ∫-6.25t+15 dt from 0 to 4 and...
Homework Statement
|x| + |y| ≤ 1
What is the region in the plane that solves this inequality?
Homework Equations
The Attempt at a Solution
I first tried graphing it by isolating the y variable
|y| ≤ -|x| + 1
Then I looked at the hint we were given, which was to assume that x and y...
Homework Statement
All vertices in a closed trail have even degree.
Homework Equations
The Attempt at a Solution
Intuitively, I know this statement is true, but I can't seem to see a clear way to show it. I know that a closed trail is a path that connects vertices, so one would follow an...
I'd like 2 solve the following problem (well, routinely solve a bunch of such problems):
Let us have a number of points (vertices), that can be interconnected. Not any 2 points are connected. Each connection is assigned a value. I want 2 find the maximum path in the graph, that is, the one with...
Homework Statement
Given that... The units of voltage are “Volts” and the units of time are “seconds”
Show τe (1/e life-time) on your graph and find a value for τe from your graph. ( The definition of τe is similar to the definition of τ1/2 (half-life))
V(t) t(s)
24 0.1
20...
Homework Statement
The figure is a snapshot graph at t = 0s of two waves approaching each other at 1.0 m/s. Draw six snapshot graphs, stacked vertically, showing the string at 1s intervals from t = 1s to t = 6s.
Homework Equations...
Hello
I'm not a professional cosmologist but I wanted to know what the orbital length is equal to in Km units in this graph: http://ej.iop.org/images/1538-4357/707/2/L114/Full/apjl334146f3_lr.jpg
Thank you so much.
Homework Statement
Use ordinary induction on k or on the number of edges (one by one) to prove that a connected graph with 2k odd vertices composes into k trails if k > 0. Does this remain true without the connectedness hypothesis?
Homework Equations
The Attempt at a Solution
If k...
Homework Statement
y = (4/3)cos(x/2 + pi/6) - (2/3)
(0 <= x < 2pi)
Find the maximum and minimum values for the trigonometry function without calculus or drawing the graph.
Basically in the solution they apply the transformations to the domain given in order to find a new domain...
So I know the shape but I forgot what its called. This is what it looks like but what is it called :L, I can't remember.
http://antonine-education.co.uk/Image_library/GCSE/Newton_II.GIF
Hey guys, so I'm having some trouble, not sure if back of the book is wrong or if I'm doing it wrong, probably me though lol.
Alright so I have this graph,
http://imageshack.us/photo/my-images/27/wqqf.jpg/It's asking me to find displacement at 10.0s.
So I know that displacement = area of a...
Homework Statement
The graph is of a runner-
time(min) is the x
position(x1000 m) is the y
these are the points
0,0
10,3
20,3.5
30,4.5
The question is- For the time interval between 10 min and 20
min, what is the runner’s displacement?
Answer in units of m
Homework...
Basing on the units, the velocity vs time is equal to acceleration. What about the velocity vs time squared and distance vs time squared graph?
Is the slope of the distance vs time squared graph one half of the acceleration? If it does, please explain.. :)
Consider the complete graph with 5 vertices, denoted by K5.
F.) How many walks of length 2 are there in graph K5? Explain.
Is this correct as follows for the walks of length 2?
K squared (2) = K x K =
0, 1, 0, 1, 0
1, 0, 1, 0, 0
0, 1, 0, 1, 1
1, 0, 1, 0, 1
0, 0, 1, 1, 0
x
0, 1, 0, 1, 0
1...
Hello, I am a high school student trying to compare two motorcycles on a displacement vs time graph.
The information I have is the mass of riders, mass of bikes, gear ratios, tyre circumference and dyno results indicating hp vs rpm. I am not taking air/rolling resistance into consideration...
Hey guys, so I have a quick question about position - time graphs, so without using calculus for let's just say a particle moving west along a horizontal straight line every 0.10 s and the displacement is 0.022, 0.032, 0.042, etc.
Well the displacement from t = 0 aren't really good numbers...
Homework Statement
Given a graph with distance (in meters) on the y-axis and time (in seconds) on the x-axis what does the area under this graph illustrate ?
The object has a velocity of 1m/s so after 5 s it has traveled 5m. Homework Equations
This is a linear line (i.e y=x) so the area can be...
Homework Statement
This is a question refer to a transistor in a common emitter configuration.
And this is the table with data of Vce and Ic at certain range of Ib stored in microsoft excel, and the graph is plotted within the file attached(in another tab)...
I'm asking this question here on a physics forum because a physics question sparked this off. However, it is applicable to all aspects of scientific knowledge.
I am looking for a scientific knowledge dependency graph. This is one centralised database which captures the specific and required...
Homework Statement
From the waveform shown below, estimate
a) the damping ratio ζ (you may compare response with a standard chart);
b) the forced or damped frequency of oscillation; and
c) the natural or undamped frequency of oscillation.
Homework Equations
Since the waveform is under...
Having a hard time with this problem. Can anyone guide me in the correct direction?
Random graphs are a fascinating subject of applied and theoretical research. These can be generated with a fixed vertex set V and edges added to the edge set E based on some probability model, such as a coin...
In a series of experiments, block B is to be placed in a thermally insulated container with
block A, which has the same mass as blockB. In each experiment, block B is initially at a certain temperature TB, but temperature TA of block A is changed from experiment to experiment. Let Tf
represent...
Hello,
Just wondering if any of you have encountered a term for a particular type of graph. It is like a graph that allows for loops, but for loops, instead of joining a vertex to itself, it joins a vertex to nothing. I just want to be consistent with existing terminology, if there are none...
i was wondering what the equation of the line/curve on a velocity vs displacement graph would be which would indicate constant acceleration.
I am totally stumped.
EDIT:please feel free to shift the thread to any other place if need be, but since it wasn't coursework this seemed to be the natural...
I am trying learn how to graph Normal distribution with TI-Nspire CX CAS went to the Ti.com but just found a work sheet. or else I missed it some where. but saw some examples on the display. thanks ahead for help:cool:
I know this proof is probably super easy but I'm really stuck. I don't want someone to solve it for me, I just want a hint.
One way is trivial:
suppose f continuous.
[0,1] compact and the continuous image of a compact space is compact so f([0,1]) is compact
Now the other...
So I'm trying to understand this paper (found here: http://arxiv.org/abs/1301.3411) but my math skills are very limited.
These include:
-Groups (the very basics, like the first of Charles Pinter's book)
-Analysis (the very basics)
But what all books/papers/topics would you suggest I...
Homework Statement
A simple type of blinking light circuit can be constructed using a neon lamp. The circuit has a 4.0uF capacitor in parallel with a neon lamp. When the voltage is low in the RC portion of the circuit, the lamp does not conduct electricity. Therefore, it is effectively not...
Hi All
As the title suggests I want to get to a level where I can approach research problems in Graph Theory. Specifically in the areas of Algebraic Graph Theory and Random Graphs. I know this is no small endeavour but I atleast want to put some direction into my extra studying.
My...