Ground Definition and 921 Threads

Hi, I'm a bit confused on how ground tracks for satellite work. I have noticed they orbit the Earth with a ground track that oscillates all around. Why is this? And why does the oscillation change in latitude for every pass around the earth. Thanks. Much appreciated.

In QM, sometimes we will combine the delta potential and other familiar potential (like infinite potential well). And I am quite confuse with the bound state. For example, consider a 1D infinite potential well with width a and locate b/w [-a/2, a/2]. Now if we add in a delta potential...

If I know the explicit form of potential, the energy and a specific eigenstate, but I don't know the general form of eigenstates and eigenvalues, can I tell if the state is ground state or not?

Homework Statement Hi all. If a system will settle into a state where the entropy is at a maximum, then why is it that the electrons in an atom will always settle for the lowest energy state, and not have an equal propability of being in either state? Is it because the entropy of the...

What regulates the ground state energy of a hydrogen atom? Why is it constant (more or less)?

Homework Statement How does a parachute help a man hit the ground with a small kinetic energy? Where does the energy go? Explain everything in energy terms. Homework Equations The Attempt at a Solution i think that when the parachute is deployed, the kinetic energy the man has...

Hi, I am trying to work out the ground run distance of takeoff for an aircraft. I can't really write the formula down because of the length and many variations of it so I am just hoping that you know what I am talking about. I am trying to work it out for a cessna 172 so i am expecting a...

Homework Statement Calculate the energy of the electron in the ground state of triple ionized beryllium, which has an atomic number Z = 4. Homework Equations -Z2 (13.6) N2 The Attempt at a Solution Z=4 as given and it is tripled so our N=3. We throw our numbers in...

Homework Statement See post #3 Assume the YoYo is a solid cylinder with mass M and radius R for all parts! Homework Equations Lots? The Attempt at a Solution Part A - Find the moment of inertia about the center of mass and the point of contact with the ground: ICOM = 1/2 MR2 IIPoC = 1/2...

Homework Statement Consider a Hydrogen atom in the ground state Find: A- The Kinetic Energy, in eV B - The Potential Energy, in eV C - The Total Energy, in eV D - minimum energy required to remove the electron completely from the atom, in eV E - What wavelength does a photon with the...

Homework Statement Al3+ N3- Li+ Au+ Sr2+ Mn2+ Tl+ Br - Homework Equations The Attempt at a Solution no clue, the positives and negatives are messing me up

Hi all. I'm working on an RF system including a 2.4G transceiver and a GPS receiver. I'll use a ground plane. What I intend to is to separate analog ground and digital ground and connect them together at the entry via a 0ohm resistor. My friend argues that a whole ground layer that connect to...

Homework Statement What are the energies of the ground state and the first two excited states of the He+ ion? Homework Equations En= - Eo/n2 The Attempt at a Solution n=1 for this problem (since there is only 1 electron) so the ground state would have the electron...

I'm building a tank circuit and I need to know if a ground connection is needed.

Homework Statement A model rocket releases its first stage when it is 100.0 m above the ground and moving upward at 40.0 m/s. Ignoring air resistance, find: the time it takes the first stage to hit the ground Homework Equations Y=Yo+VyoT+1/2GT^2 Quadratic The Attempt at a...

Homework Statement I just want to know if there is a relationship between the ground state of Hydrogen which is 13.6 eV and the ground state of Helium. The problem is asking me to find the ground state of Helium, but I am not sure how to go about it. Any advice? Homework Equations...

Homework Statement A hellicopter traveling upward at 69 m/s drops a package from a height of 500 meters. To the nearest second how long does it take to hit the ground? Homework Equations possibly displacement?? v= 69 x=500 a=9.8 t=?? The Attempt at a Solution do i use X=1/2...

Homework Statement I have been given the Hamiltonian H = \sum_{k} (\epsilon_k - \mu) c^{\dag} c_k where c_k and c^{\dag}_k are fermion annihilation and creation operators respectively. I need to calculate the ground state, the energy of the ground state E_0 and the derivative...

How does one calculate the distance (or length) on the ground suspended by one minute of arc (or one second of arc) at a particular point on the Earth's surface,given its latitude/longitude in degrees/ minutes /seconds ?.Where would one get the Earth radius of sufficient accuracy as a function...

Prove that the flange of a train wheel moves backwards in respect to the ground, using the trigonometric functions, linear and angular velocity I really have no idea to go about doing this, all I know is that the proof involves some use of trigonometric functions, linear and angular velocity

Hey, I'm currently in a physics class (im not real good at it hah). And a lot of times out of class i think and relate things to what I have learned... Well, me and some friends were talking about tasers, and I was wondering if it were possible for multiple people to connect (hold hands...

This is what I've tried to work out and I'm not getting -13.7 eV. What am I doing wrong? E 2 Π m e^4 / (4 Π ε0 )^2 h^2 6.90E-19 J=4.31eV m 9.11 x 10-31 kg 9.11E-31 e 1.60 x 10-19 C 1.60E-19 ε0 8.85 x 10-12 C2/Nm2 8.85E-12 h 6.63 x 10-34 J S...

[b]1. Homework Statement [/ What happens to the kinetic energy of a projectile when it hits the ground Homework Equations The Attempt at a Solution

Homework Statement King Arthur's knights fire a cannon from the top of the castle wall. The cannonball is fired at a speed of 45m/s and an angle of 32degrees . A cannonball that was accidentally dropped hits the moat below in 1.4s . a) How far from the castle wall does the cannonball hit...

Homework Statement Seven electrons are trapped in a one dimensional infinite square well of length L. What is the ground state energy of this system as a multiple of h2 / 8mL2?Homework Equations Energy of a single electron in state n is n2h2 / 8mL2The Attempt at a Solution Pauli exclusion...

While driving North at 25 m/s during a rainstorm you notice that the rain makes an angle of 38 degrees with the vertical. while driving back home moments later at the same speed but in the opposite direction, you see that the rain is falling straight down. From these observations, determine the...

Homework Statement A 35.5 kg parachutist lands moving straight downward with a speed of 3.85 m/s. (a) If the parachutist comes to rest with constant acceleration over a distance of 0.700 m, what force does the ground exerts on her? Variables: Vo, Vf, F, m, a, x Known: Vo=3.85 (I think the...

Homework Statement From serway's book chapter 23(electric fields), questions section. Homework Equations --- The Attempt at a Solution The obvious answer would be that it is safe because the student holding the sphere is insulated from the ground, but what does that really mean ? If I try to...

Homework Statement A stone is launched straight up by a slingshot. Its initial speed is 20.2 m/s and the stone is 1.40 m above the ground when launched. Assume g = 9.80 m/s2. A: How high above the ground does the stone rise? B: How much time elapses before the stone hits the ground? Homework...

Homework Statement A hot air balloon is rising upward with a constant velocity of 4m/s. As the balloon reaches a height of 4m above the ground the balloonist accidently drops a can of pop over the edge of the basket. How long does it take the pop can to reach the ground? V2 = 4m/s [up] v1...

Hi everyone, This question is from my problem set this week in my Phys 371 class. Any help, hints or ideas would be very much appreciated! "Use the Heisenberg Uncertainty Principle to estimate the ground state energy in the hydrogen atom. Since the wave function that solves this problem is...

Hello, yes another GROUNDING question :) Can anyone tell me why lightning wants to travel to the Earth? and what happens to all that current that it carries after going into the Earth. Like what does the Earth do with it.. are there positive ions that neutralizes everything or what?

[Ground"Ed" vs. Ground"Ing"] Why does the ground"Ing" wire in a circuit draw high amounts of current and trips the breaker when a ground"Ed" (neutral) wire does not?

I do not understand the concept of electrical ground, or why it works. Let me explain. In elementary school physics, one learns that for a current to take place, you need a battery with positive and negative poles. This creates a voltage that makes charges run from plus to minus, because...

I am about to install an electric outlet . There are three wires to and I am not sure which one is the ground wire . All wires having the same color ! How can I determine which one is the ground ?

Hi, please let me know the purpose of having a ferrite bead isolation for ground (between digital and power)? as far as i understand. the ferrites will be helpful in case of power noise filtering. And noise from digital line return path wouldn,t affect the power levels as it might do for...

If two objects of equal mass are dropped...one from h1 and the other fro h2...will they hit the ground with the same force? Because the only force acting on the objects is gravity so we can say: F=ma and the acceleration is constant...so the forces must be the same. Is this correct...

Homework Statement A baseball is hit at ground level. The ball reaches its maximum height above ground level 3.6 s after being hit. Then 3.1 s after reaching its maximum height, the ball barely clears a fence that is 87.5 m from where it was hit. Assume the ground is level. (a) What maximum...

[b]1. At a particular instant, a stationary observer on the ground sees a package falling with speed v1 at an angle to the vertical. To a pilot flying horizontally at constant speed relative to the ground, the package appears to be falling vertically with a speed v2 at that instant. WHAT IS...

When kicking off the ground, what is the maximum amount of force that human's can exert? Any references?

[SOLVED] Airplane propeller and plane's velocity relative to the ground. Homework Statement An airplane propeller rotates at 2200 rev/min while the airplane flies at a speed of 550 km/h relative to the ground. The plane's velocity is parallel to the propeller's axis of rotation. Part a)...

[SOLVED] A box of mass 8.0kg is being dragged along the ground by a force of 30N. [FONT="Georgia"][SIZE="3"]Homework Statement A box of mass 8.0kg is being dragged along the ground by a force of 30N. (a) If the friction force is 26N what is the resulting acceleration? (b) If the frictional...

Homework Statement 1 A light plane is traveling at 175km/h on a heading of 8° east of north in a 40-km/h wind from 80° east of north. Determine the plane's ground velocity. Homework Equations cosine law The Attempt at a Solution I found the resultant to be 191 km/h but the...

[SOLVED] Perturbed Ground State Wavefunction with Parity Homework Statement A particle is in a Coulomb potential H_{0}=\frac{|p|^{2}}{2m} - \frac{e^{2}}{|r|} When a perturbation V (which does not involve spin) is added, the ground state of H_{0} + V may be written |\Psi_{0}\rangle =...

Hello All, I was talking to a friend about how to properly isolate a digital board from a high-powered output stage. The output stage in my application make square wave pulses that can be as high as 500V. So my first thought was to galvonically isolate the output stage circuitry from the...

(1) How do you identify Ground roll on a shot record? Is it just the polarized nature of the ground roll that leads to its recognition on a shot record? (2) What is the importance of the Fresnel zone? and What does it depend on?

Homework Statement Given the attached scheme, if R_{1}=R_{2}=R_{3}=10 Ω and \epsilon_{1}=20 V , \epsilon_{2}=10 V determine the potentials at the points A,B,C,D,E. The sources of emf have no internal resistance. Homework Equations My question is: Why is it that no current exists along...

so I had this thought earlier today. I am not claiming this is true or even likely but its interesting, possible (from everything I know), and may be testable by experiment. What if annihilation doesn't actually exist? What if what we see as an electron annihilating with a positron is...

I got a question regarding ground in terms of a power supply and another one with regards to PCBs. Usually you see people put a jumper cable between the negative terminal of a power supply to common ground. Why do people do this? Is it for the user to reference the power supply to actual...

Homework Statement a 3 kg ball is dropped from rest from the roof on a building 176.4 m high. While the ball is falling, a horizontal wind exerts a constant force of 12 N on the ball? Part 1) How long does the ball take to hit the ground? Part 2) How far from the building does the ball hit the...