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I often do circuit. But still there is always stuff i dont get..

I was asked to find

1) I1 I2 I3 immidiately after S closed

2) I1...

Find the transient current in this circuit]]>

I hope I am asking this correctly.

TIA

Clark]]>

An uncharged nonconductive hollow sphere of radius 10.0 cm surrounds a 20.0 µC charge located at the origin of a cartesian coordinate system. A drill with a radius of 1.00 mm is aligned along the z axis, and a hole is drilled...

Homework Help: Find the Electric Flux Through a Hole In a Sphere]]>

The moment of inertia about an axis through the center of mass of a system consisting of two masses 3.0 and 5.0 kg connected by a rod of negligible mass 0.8m long is

I = I1 + I2

Moment of inertia of a system of masses]]>

3)Earth is accelerating and decelerating in its orbit around the sun all the time and yet we don't feel it, why? Is it only...

Acceleration and its effect on matter.]]>

As a third year undergrad I feel pretty alone. My fellow colleagues are not very forward thinking nor want to do anything besides pass the exams.

Are there any platforms/associations for young theoretical physicists?...

Platform for theoretical physicists?]]>

10,000 black holes near Sagittarius A ?]]>

1) Why measurement appears to cause a discontinuous change in the wave function for a single quantum entity/system?

As in Schrodinger, "The abrupt change by measurement … is the most interesting point of the entire theory…in the realism...

Measurement problems?]]>

I want to start an Aerospace Company]]>

If the height of a frictionless incline is h. Determine the work done by the force due to gravity F as the crate of the mass m slides down the incline

W=Fd cos (theta )

Force due to gravity...

Determine the work done by the force due to gravity]]>

How to erase data?]]>

1. The problem statement, all variables and given/known data

An electron in a one-dimensional infinite well in the...

Expectation values and probabilities for spinors in a well]]>

1) How do we go about finding the keys when joining , say, 5 tables at a time? Does one do a database diagram using those tables?

2) I am having trying to set up the diagrams for these...

Large Joins in Large Databases. How to find Keys?]]>

Using covariant derivative formula for covariant tensors and covariant vectors. which are

##∇_av_b=∂_av_b-{Γ^c}_{ab}v_c##

##∇_aT_{bc}=∂_av_{bc}-{Γ^d}_{ac}v_{db}-{Γ^d}_{ab}v_{dc} ##,

I got these:...

Riemann curvature tensor derivation]]>

A vessel contains a mix of helium and nitrogen (ideal gases). The ratio of the partial pressures is known: ##\frac{p_{N2}}{pHe} = 5##. The partial pressure is the pressure that a single component alone would exert.

Gas mix of helium and nitrogen]]>

How is medical physics compared to other fields of physics?]]>

But Jupiter's gravity is more than the Earth's gravity, although its density is lower?

Is the sun's gravity more than the Earth's gravity, even though the intensity of...

What is the relationship between gravity and density?]]>

A four bar chain is arranged as the diagram shown below If the input link AB rotates at 400 RPM anti CW determine the angular velocity of link DC

See attached photo...

Four Bar Linkage Mechanism - Space Diargram]]>

I am a science writer. I am particularly interested in physics history,...

Rapscallion neophyte intro]]>

https://www.forbes.com/sites/lizrya...out-why-nobody-wants-to-hire-me/#bc7fb028866f

Every year the population growth rate is 5% per year.

y' shows the growth rate of the y (population).

Since the population grows by 5% every year, the growth rate is:

y' = 0.05y.

This is a simple differential equation.

When y(0)...

What's the difference between 1000e^0.05t and 1000*1.05^t?]]>

(I) the velocity of the piston relative to the fixed point O (V bo)

(ii) the angular velocity of AB about point A (Wab)

iii) the acceleration of point B relative to...

Offset slider question]]>

I've been tasked with computing binary star orbits based on their initial parameters, positions and velocities.

In this problem everything must be expressed in terms of the masses, but I am struggling to define positions and velocities in terms of mass.

It is assumed that the stars are...

Binary Star initial positions and velocities]]>

two rail cars are coupled together, each weigh 82500 lbs. They are on tracks at a 0.499% grade. each rail car has 2 trucks of 2 wheels each, for a total of 16 wheels. The assumed force of friction for contact with the wheel...

Does the railcar move?]]>

Four equivalent charges are placed at (0,0), (a,0), (0,a), and (a,a). What is the electric field at point B (a, a/2)?

View attachment 224288

My attempt:...

Finding the electric field at point - Can someone check my work?]]>

I don't understand the term "enumerable" though. The...

Please explain "enumerable"]]>

I have a problem understanding the equation

$$\Delta V = -\int_{a}^{b} \vec{E} \cdot d \vec{l}$$

In the case of a parallel plate capacitor whereby the positive plate is placed at ##z=t## while the negative is at ##z = 0##, my...

Problem with line integrals for electric potential]]>

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Hi All!

This is probably going to have a very simple answer. I'm stuck on question (b)(ii). The only equation I can find with the...

Optics - Diffraction grating]]>

I need some guidance on how to actually carry out the calculation of the power...

How does one actually compute a correlation function?]]>

I've talked with a mentor of mine about...

Curious question regarding Faraday disc / induction, etc.]]>

Is quantum physics "retro-deterministic"?]]>

For a single mechanical unit lung, assume that the relationship among pressure, volume, and number of moles of ideal gas in the ling is given by P

Derive lowest order (linear) approximation]]>

Suppose you have a tank 10 m high. The tank is currently filled 5 m high with 1000 kg of water. How much energy does it take to pump in another 1000 kg of water from the bottom to fill the column to 10 m? (Ignore friction, etc.)...

Pumping water upwards in a column]]>

So i thought about some other stuff and then somehow this idea appeared to me, now according to physics it is impossible to communicate information faster than the speed of light through vacuum which is "c".

So for any two bodies moving in...

FTL train + FTL communication thought experiment]]>

At the top of a mountain the temperature is -5 degree C and a mercury barometer reads 566 mm, whereas the reading at the foot of the mountain is 749 mm.

Assuming a temperature lapse rate of 0.0065...

Using Pressure and Temperature differences to find height]]>

.... or AA! :)

We have had contests on the Alphabets where each photo posted must have a theme in sequence with the alphabets. We also had separate contests on photo association, where subsequent photo must have a clear association...

PF Photo Contest - Alphabets Association (4/21-4/27)]]>

Is Shear Stress Vertical or Horizontal in I-Beam Webs?]]>

Does it mean above effect used at photographic camera lens design to make that lens sometimes works like polarizer filter ?

Mustafa Umut Sarac

Istanbul]]>

P.S. to celebrate becoming an Established Member of this great community I had to post something fun.]]>

This dumb video is making the rounds of the dumb.

Apparently, it's not enough to promote that water goes down the drain in different directions in different hemispheres, but now apparently, you only need to go

More rotating toilet bowl insanity]]>

For wave power, electrical power generation has to be on shore not in...

Wind Turbine Hydraulic to Electrical Conversion]]>

Hi

I am looking at part a).

View attachment 224494

below

I can follow the solution once I agree that ## A^u U_u =0 ##. However I don't understand...

Tensor Covariant Derivative Expressions Algebra (Fermi- Walk]]>

View attachment 224416

m:mass of solid cylinder

T: tension in string

w:angular velocity

m(g-a)=T

mg-ma=T

a=v^2/r=w^2r

now what?]]>

Can I just confirm that when we associate a T-L KvF with energy it should be the form ##\dot{t}^2## and not ##\dot{t}##, since I have seen a mix of the notation amongst notes/books, well with just one example using just ##\dot{t}##, I suspect it must be the ## \dot{t}^2 ## , since...

Time-like KVF and Energy GR]]>

In Young's double slit experiment, there are two things I cannot explain. Any help is appreciated!

The first one is why the bright fringes get dimmer as you get further from the central/brightest spot. My theory, after looking in the two books I have, is that each single slit decreases...

Young's double slit: why it gets dimmer and inconsitent?]]>

How I can ask questions]]>

Good article for novices - 10 Tips For Growing Your Own Food In Your Garden

https://www.yahoo.com/food/the-10-tips-for-growing-your-own-food-in-your-118376985826.html

This is a continuation of the original thread...

How does your Garden grow? part 2]]>

One of my wheelchair motors overheats and stops working]]>

Would you rather...

Have lunch with Issac Newton

or

Albert Einstein]]>

Lets say I have N independent, not necessarily identical, random variable. I define a new random variable as

$$Y=Σ^{N}_{i=0} X_{i}$$

does Y follow a normalized probability distribution?]]>

I have some difficulties understanding a formula for calculating the incidence angle for incoming solar radiation on a sloping surface. I found that:

angle of incidence calculated as cos(j) = sin((pi/2)-surface slope)*sin(altitude angle) + cos((pi/2)-surface slope)*cos(altitude...

Calculating the incidence angle of the Sun]]>

Perpetually driven electric car]]>

Ask the Advisors: What's Your Most Memorable Textbook?

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...

Ask the Advisors: What's Your Most Memorable Textbook? - Comments]]>

Limit of an extension]]>

Gravitational force exerted on mass

Orbital velocity at distance R from earth = ##\sqrt gR##

Escape velocity = ##\sqrt 2gR##

gR = GM/R

Fc = mV^2/R

F =m.a

Find the speed of a satellite at a distance R from Earth]]>

According to this article,metals are good reflectors at low frequencies.What about at high frequencies like visible or UV spectrum?Will this show deviation]]>

Many hot-water heating systems have a reservoir tank connected directly to the pipeline, so as to allow for expansion when the water becomes hot. The heating system of a house has 63.1 m of copper pipe whose inside radius is...

Thermal expansion of a copper pipe]]>

Beam Fixed at Both Ends]]>

Calculate the pH of the following solutions: (caution: these are hydrolysis reactions)

a. an 0.30 M solution of NaF

I think by hydrolysis reactions they mean that each of the given...

Calculating the pH]]>

The exercise asks many questions about the following E(k) diagram, but i'm more interested in understanding some basic things about it, from which I'm sure i'll be able to find the answers i'm requested....

Interpretation of electronic bands in a solid]]>

Harmonic Oscillator and Volume of Unit Cell in Phase Space]]>

View attachment 224481

I only need help on part c. I tried to add up t1 and t2 and differentiate it. However what variables should I differentiate with...

Deriving the Lens Maker formula of a plano-convex lens using Fermat's Principle]]>

"If, when we have lifted and lowered a lot of weights and restored the machine to...

Perpetual motion machine - Intuitive meaning]]>

Thanks for any replies :)]]>

So let's consider a diffeomorphism generated by a vector field ##V##. If ##X## is a point on our manifold,...

Coordinate representation of a diffeomorphism]]>

A meter stick has a mass of 0.2kg. A small hole is bored in it at the 10cm mark so the meter stick can be hung from a horizontal nail. The moment of inertia of the meter stick around an axis at the 10cm mark is

Moment of inertia of a meter stick]]>

Ignoring air resistance, if it takes 16 seconds for a package to strike the ground, how high above the ground was a package when it was thrown upward from the stationary helicopter at 15 m/s per second

How high was the package above the ground when it was thrown]]>

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Hi

I am looking at this quesiton attached part c).

2. Relevant equations

I can by my notes which tell me that if I reach a column with a negative...

Operations Research: Simplex table, unbound optimal solution]]>

Galileo claimed that a body could not "by itself" change the state of rest or uniform rectilinear motion of its center of gravity.

Newton clarified this with the notion of force and inertia. F = m.a.

So let's follow a mass m.

Either a closed container containing a gas. And one of the...

Change in speed]]>

When it is a particle, what actually is it? is it literally like a tiny physical ball rattling around? (If not, then what is it?)

And when it is a wave, what is it?

From my understanding, when a particle behaves like a wave, the...

What is a subatomic particle?]]>

You are detained and there are two doors in front of you, one leads to death and the other to freedom. Each door is guarded by one deputy. One of the deputies always makes false statements while the other always...

What question should you ask?]]>

Hi, initially I am aware that magnetic flux is conserved due to divergence of magnetic field is zero and for long solenoid, magnetic field inside is uniform. So magnetic field intensity (B) at point P,Q,S, T,R,U(in the attachment) must be same. But my question is :...

Magnetic flux is the same if we apply Biot Savart?]]>

In the central region of a solenoid that is connected to a radio frequency power source, the magnetic field oscillates at 2.5·10^6 cycles per second with an amplitude of 4 gauss. What is the amplitude of the oscillating...

Maximum electric field from magnetic field]]>

I don't know how I would make a driver for such a thing. Would it need to be software driven for example? Any input to point me in the right...

Rolls Royce permanent magnet thruster questions]]>

View attachment 224418

Boundary condition

EI(d^4y/dx^4)=w

Boundary condition:

At A, x=0, y=0, slope=0

At C, x=L/2, y=0, shear force = -Rb

At B, x=L, y=0,...

3 supports beam problem]]>

Name the Science Book Author

View attachment 219690

Continue reading the...

Name the Science Book Author - Comments]]>

Calculate the pH of a 0.20 M solution of iodic acid #(HIO_3)#. #K_a# for iodic acid is 0.17

#K_a = \frac{[H^+][IO_3^-]}{[HIO_3]}#

#[HIO_3] = 0.20# M.

The...

Calculate the pH of a 0.20 M solution of iodic acid (HIO3).]]>

Should I Read The Feynman Lectures?]]>

Kinetic energy per mol is 3/2KT

Q = nC##\Delta##T

U = Q + W

W = -P##\Delta##V

1) internal energy = 3/2NKT

2) heat needed to increase temperature of 1 mol ideal...

Heat and work when temperature increases by 1 degree]]>

I am transferring over to ASU from a community college and have declared physics as my major. This is something I have planned on for a while because I am...

Physic undergrad and material minor?]]>

I just came across this fun anecdote that I can't resist sharing. It reminds me of the many threads we get here on PF asking about novel ways to generate electricity.

[QUOTE="From:...

Young Edison, or Edison's cat]]>

Butanol at a temperature of 28 C is pumped at a velocity of 14 m s-1 through a 100 mm diameter tube kept at a wall temperature of 90°C. The properties of butanol are given below.

Determine the convective heat transfer...

Heat Transfer problem: Butanol running through tube]]>

if a beam fixed at two points is on an angle say 45 degrees from the x or y axis instead of running parallel to x axis in most questions does this effect calculations? The force acting upon it would be a load directly downwards...

Does the angle of a beam fixed at two points affect the method?]]>

How to hook up my PC to my TV]]>

Could someone please see if my working are correct for this question, I have never actually done a question of this nature before, and after reading up about the derivation on the perturbation I thought I give ago and apply, my...

Perturbation of a Magnetic Field]]>

Relationship between mass and acceleration]]>

A=*pie* x 0.2 ^2

A=*pie* x 0.04

A= 0.1256 m^2

A=*pie*x r2

A=*pie*x (50 x 10^-3)2

A=*pie* x 0.05 ^2

A=*pie* x 0.0025

A= 0.00785 m^2

P= p x g x h

p=1000 x 9.81 x 5

p= 49.05 kpa

p= f/a

p= 1000/0.1256m2

p=7961.78kpa

7961.78- 49.05 = 7912.73 kpa

F = P x...

dead weight tester calculation help]]>