Do laws of physics apply below
the event horizon? It appears as if
black holes had such gravity as to have an
escapr velocity higher than c, which means that
things are pulled inwards at higher speeds than
the speed of light. Or am I overlooking something?
So it seems there is predilection in physics to go after simple and elegant models of physical reality. That is, parsimonious models are preferred. Sometimes this means that there is a trade off between mathematical elegance and intuition.
For example, if theory A and theory B both perfectly...
Not saying that there is another universe. But if there were, would the laws be the same?
I've heard Leonard Susskind explain that extraneous solutions of string theory could represent the environment in regions very far "away".
So is it just small things like the physical constants being...
Homework Statement
[/B]
A boy with a mass of m1 is sitting in a carousel. The spinning frequency is 0.3355. The boy is also sitting on a weighing scale, will they show a number higher than m1g,lower or the same? (The mass of the weighing scale is 0).
Homework Equations
mω2r=F
ma=F
ω2=4π2f2...
Homework Statement
Max (65 kg) pushes Toni (50 kg) with a force of 360 N. The force of friction is 0 on Toni and 80 on Max.
(a) Find each girls acceleration
(b) If Max pushes Toni for 0.1 s, how far will Toni travel in 0.5 s?
Homework Equations
Fnet=ma
v2=v1+at
d=v1(t)+1/2a(t)^2
The Attempt...
Homework Statement
Homework Equations
Kirchhoff;s first and second law, V=IR
The Attempt at a Solution
Tried the question as follows:
V= 24/(2+6+4)
= 24/12 = 2V (pd from top cell)
then did 2=4 I3
therefore I3 = 0.5A
and then 2 = 6I2
I2 = 0.33A
and I1 = 0.5+0.33...
=0.83A?
Homework Statement
Homework Equations
V=IR and kirchhoffs laws
The Attempt at a Solution
Number three is my attempt at finding a solution but I got stuck when I had to find an expression for loop one on the diagram. Thanks in advance for your help...
Suppose we have a body of finite size which can be translated, rotated, compressed and stretched. We have every information about the body. We have its dimensions and everything. We have its mass and density. But, since I'm here talking about a completely generalized version, so we have variable...
1. Homework Statement
A DC circuit is shown below. Note the ground (V=0) in the circuit
1- calculate the current through the 5Ω resistance. Use "+" sign for the current directed from right to left, and "-" sign if the current flows from left to right.
2- The sign of the potential at a is...
Homework Statement
Homework Equations
F=m*a
ΣF=0
The Attempt at a Solution
Firstly, I tried to work on the normal force of bowling ball. But I can't get the answer. I don't get the idea that bowling ball could be kept at constant height, I didn't really understand the question guess. Can...
I've lately began working with Newtons laws problems at school again, and I've already ran into a few problems.
When making calculations and solving problems, it is often nessecary to understand when forces are equal to zero, and when they are not. Since every force has an equal and opposite...
I'm an attorney trying to invalidate a patent that I believe is directed to patent-ineligible subject matter. It's been an interesting exercise, and I'd love to hear other ideas/suggestions/etc. on how to approach it.
At a high level, the patent claims certain structures with a certain...
Homework Statement
Determine Currents ##I_{1}, I_{2}, I_{3}##
Homework Equations
Kirchoff's Rules:
$$\sum_{i=1}^n I_{i} = 0$$
$$\sum_{i=1}^n V_{i} = 0$$The Attempt at a Solution
Basically, I'm not sure if I'm applying the Loop Law correctly. For example, in Loop A, going clockwise from...
I am hoping that I can have someone look over my answers. I have provided what I think is necessary to be appropriate posting, including the questions and attempts at all my answers. I would just like some feedback that I am correct in my answers. Thank you!
This is an overview that all the...
Consider a 4 current
J^\mu and a metric g then conservation laws will require \del_\mu J^\mu = 0
my lecturer gave me a brief problem and I think I'm missing some understanding of it
he writes
What I'm not understanding is, where he states, if we choose B to be the time slice between etc...
Hello,
So, I'm posting this question here because I can't think of a better place, and also here there are people from all over the globe.
The thing is, I'm doing some research on Delivery of Goods and Laws related in Brazil. But, to have some base, I want to make some comparisons with laws...
Homework Statement
One or more external forces are exerted on each object enclosed in a dashed box shown in the figures below. Identify the reaction to each of these forces, assuming that (b) occurs on Earth. Select all that apply.
(b) the wagon exerts a force
· downward on the Earth...
Homework Statement
Consider a uniform rod of mass 12kg and length 1.0m. At it's end the rod is attached to a fixed, friction free pivot. Initially the rod is balanced vertically above the pivot and begins to fall (from rest) as shown in the diagram. Determine,
a) the angular acceleration of...
Homework Statement http://postimg.org/image/ys43ylstp/ [/B]
I need to find tension and current in each element of the circuit. I have included an image of what I have drawn so far for the circuit. http://postimg.org/image/ys43ylstp/
Homework Equations
Kirchoff's laws.
The Attempt at a Solution...
Hi.
In the (mainstream) books of electrodynamics I know, the electric and magnetic fields are introduced as force fields normalized to a charged test particle of 1 C. This makes those fields appear as an unnecessary, but convenient mathematical tool. They cannot be measured in the absence of...
Here's a thought from other thread
A reply
So what's the relation between gravity and the laws of thermodynamic, or should it be conservation of energy?
Reading the English translation of Einstein's seminal paper on GR.
http://einsteinpapers.press.princeton.edu/vol6-trans/90?ajax
This paragraph below on p78 doesn't make much sense to me.
Could you provide a second English translation or even adding math notation.
"Before Maxwell, the laws...
Homework Statement
The electric and magnetic fields of a 1 Coulomb charge Q are measured by a pair of field measuring instruments. From the perspective of observers in frame O, the charge is at rest at the origin and one of the field-measuring devices is also at rest, with position (x,y,z) =...
Hello everyone!
I want to proof that:
##p \land (p \to q) \Rightarrow q##
I know this is a quite trivial problem using truth tables, however, I want to do it without it. As I'm learning this myself, is this the correct approach?
##p \land (p \to q)##
##\iff p\land (\neg p \lor q)##
##\iff (p...
Homework Statement
A block of mass ## m ##, attached to a rope, is dropped at the point A.
When the block reaches the point B, the tension is ## T = 2 \cdot m \cdot g ## and the rope broke at that same point.
If the length of the rope is ## L = 6cm ##, evaluate the height ## h ## where the...
I've been noticing that there are exceptions to every scientific law. For Example, with Newton's First and Second Laws are totally invalid at the quantum level, but I'm failing to find such an example for Newton's Third Law. Is anyone able to help me?
9/1/2016 Orbital mechanics Wikipedia, the free encyclopedia
This reference states:
"General relativity is a more exact theory than Newton's laws for calculating orbits, and is sometimes necessary for greater accuracy or in highgravity situations (such as orbits close to the Sun)".
Can GR...
So, I'm reading a physics book, and it talks about Newton's three laws, of course, but then after that it says that if a force of f pushes on an object at angle Θ, then the force in the x direction is f ⋅ cos(Θ), and the force in the y direction is f ⋅ sin(Θ).
Where did THAT come from? Do we...
Homework Statement
The chain comprising three rings (each of mass ##0.25kg##) is suspended from a massless rope, and a pulling force ##\left(F=9N\right)## is exerted upwards on the rope. Picture: http://i.imgur.com/xeaiBsc.jpg?1.
I need to find the values of all the unknowns.
Homework...
Homework Statement
Two cardboard boxes full of books are in contact with each other on a friction less table.Box H has twice the mass of Box G. If you push on box G with a horizontal force F, then box H will experience a net force of?
2. The attempt at a solution
Let book G's mass be = m...
Dear All Gravitinos,
It seems that the current string theory and loop gravity's explanation for the micro-states of black
holes are all quantum mechanical and have no classic correspondence. I, in this day's arxiv, post a
pure classic interpretation for this question, titled "Black...
Howdy,
Was wondering if you guys would mind critiquing, correcting, or adding any good insights to the following which was posted elsewhere by me, thanks!
________________
... remember a ways back there was a finding that went viral about the speed of light not being constant? I forget the...
Within the context of Newton's laws, it seems implicitly understood that mass is an additive property of objects.
My question is: should this be considered "just" an experimentally confirmed fact, or is is provable from Newton's laws?
The following is a more precise context for this question...
Hello all, I have perused this forum for a while now. I've never signed up because I have nothing to offer you folks. I'm not evan an amateur, I'm just interested in physics. I'm a critical care / flight medic, so my understanding of physics is really, really, really limited. Although, I'm...
Homework Statement
A resting hockey puck is hit with a force of 15.3 N. The frictional force slowing the puck down is 1.0 N.
a) Find the net horizontal force acting on the puck while the stick is in contact with the puck.
b) If the puck leaves the stick with a velocity of 45 m/s, how far will...
Im just reading this one example and i am stumped at this one step.
(R\to C) \land (S \to C) \\
(\neg R\lor C) \land (\neg S \lor C) \ \ \ \ \ \textrm{by conditional law}\\
(\neg R\land \neg S) \lor C \ \ \ \ \textrm{by distributive law}
I don't understand how it went from the second step to...
Homework Statement
there are 2 formula of vont karman and prandit laws to find the friction factorfor rough pipe and smooth pipe , which formula should i use for this question?
.
P/ s : I'm asked to find the friction factor using the vont karman and prandit laws.
Homework EquationsThe Attempt...
Homework Statement
Wasnt able to upload file, therefore an external link
https://drive.google.com/file/d/0B0FIIKckKOcKWFcxcmtJRVRXZTA/view?usp=drivesdk
A force F= mg is applied on C, all pullies are frictionless and we need to find the reading of the spring balance, basically the tension...
Homework Statement
Let ##x \in G## and ##a,b \in \mathbb{Z}^+## Prove that ##x^{a+b} = x^a x^b##.
Homework EquationsThe Attempt at a Solution
If I am not mistaken, we would have to do multiple induction on ##a## and ##b## for the statement/proposition ##P(a,b) : x^{a+b} = x^a x^b##. First we...
Hi,
I'm currently making a three-body simulator and I'm trying to add the eccentricity to Kepler's Law to turn the circular orbits to more of a elliptical orbit? I'm using Newton's Law of Gravitational to plot the new positions. How would I add in the eccentricity to this equation? I'm...
Homework Statement
All the surfaces shown in fig. are assumed to be frictionless. The block of mass m slides on the prism of mass M which in turn slides backwards on horizontal surface with acceleration of ao. Find the acceleration of smaller block with respect to prism.
Homework...
Hi, I'm a frehshman in High school writing a paper about Isaac Newton. One of my paragraphs is about the laws of motion. I came across a tidbit of information - there are instances in which Newton's laws are not correct. One example I found was that, at speeds approaching that of light, an...
I find difficulties in identify the forces acting behind the acceleration of objects that are considered consequence of conservation principles (for istance of KE and angular momentum). I'll make an example to explain. The same string-mass system is linked to a rod. In case (a) a force pull the...
Must an initial state always be mapped onto exactly one final state and vice versa?
Consider a slope that is shaped like a curvy "w". Releasing a ball from either end will result in the same final state where the ball is stationary at the highest point in the middle. So does it mean that...
Homework Statement
Given a battery with voltage 35.7 V and 4 Resistors (Top left with resistance 2R, and the 3 others each with resistance R) where R = 507 Ohms, what current would an ideal ammeter read in its current position? (Diagram attached)
Homework Equations
Kirchoff's Laws: KCL and...
Homework Statement
The picture has the problem question.
OK.
When the moon is at point B, the distance from the moon to the center of the planet is most nearly:
A) (1/25) * rA
B) (1/5) * rA
C) (1/ sqrt(5) ) * rA
D) rA
E) sqrt(5) * rA.
Homework Equations
Newton's law of gravitation...
I think this may have been done before. So people are aware of the geometry of reflection. If I go beyond, I try to say that if light can pump electrons, it is absorbed, if it merely polarizes, it gives rise to an alternating dipole supposed to be polarizing the region around in all directions...
Homework Statement
You tie a cord to a pail of water, and you swing the pail in a vertical circle of radius 0.700 m
What minimum speed must you give the pail at the highest point of the circle if no water is to spill from it?
Homework EquationsThe Attempt at a Solution
I got the correct answer...
Homework Statement
Consider the system shown in the figure (Figure 1) . Block A weighs 46.1 N and block B weighs 28.7 N . Once block B is set into downward motion, it descends at a constant speed.
http://session.masteringphysics.com/problemAsset/1038576/6/YF-05-54.jpg
A
Calculate the...