Induced seismicity refers to typically minor earthquakes and tremors that are caused by human activity that alters the stresses and strains on the Earth's crust. Most induced seismicity is of a low magnitude. A few sites regularly have larger quakes, such as The Geysers geothermal plant in California which averaged two M4 events and 15 M3 events every year from 2004 to 2009. The Human-Induced Earthquake Database (HiQuake) documents all reported cases of induced seismicity proposed on scientific grounds and is the most complete compilation of its kind.Results of ongoing multi-year research on induced earthquakes by the United States Geological Survey (USGS) published in 2015 suggested that most of the significant earthquakes in Oklahoma, such as the 1952 magnitude 5.7 El Reno earthquake may have been induced by deep injection of waste water by the oil industry. A huge number of seismic events in fracking states like Oklahoma caused by increasing the volume of injection. "Earthquake rates have recently increased markedly in multiple areas of the Central and Eastern United States (CEUS), especially since 2010, and scientific studies have linked the majority of this increased activity to wastewater injection in deep disposal wells."Induced seismicity can also be caused by the injection of carbon dioxide as the storage step of carbon capture and storage, which aims to sequester carbon dioxide captured from fossil fuel production or other sources in Earth's crust as a means of climate change mitigation. This effect has been observed in Oklahoma and Saskatchewan. Though safe practices and existing technologies can be utilized to reduce the risk of induced seismicity due to injection of carbon dioxide, the risk is still significant if the storage is large in scale. The consequences of the induced seismicity could disrupt preexisting faults in the Earth's crust as well as compromise the seal integrity of the storage locations.The seismic hazard from induced seismicity can be assessed using similar techniques as for natural seismicity, although accounting for non-stationary seismicity. It appears that earthquake shaking from induced earthquakes is similar to that observed in natural tectonic earthquakes, although differences in the depth of the rupture need to be taken into account. This means that ground-motion models derived from recordings of natural earthquakes, which are often more numerous in strong-motion databases than data from induced earthquakes, can be used. Subsequently, a risk assessment can be performed, taking account of the seismic hazard and the vulnerability of the exposed elements at risk (e.g. local population and the building stock). Finally, the risk can, theoretically at least, be mitigated, either through modifications to the hazard or a reduction to the exposure or the vulnerability.
A bar magnet is being pulled away from one end of a solenoid, eg N pole of magnet nearest to solenoid. I've learned that the current induced in a solenoid is such that the magnetic field it creates opposes the change in flux through the loop. But what if the solenoid is in an open circuit? Will...
Ok, now I got another question while doing electromagnetic induction questions.
I know flux linkage=NBA and in a rotating coil, Flux linkage=NBA cos wt, which differentiated (Faraday's Law) wrt time gives E=NBAw sin wt, where w = angular frequency.
However, when the plane of the coil is...
[b]A steel alloy specimen having a rectangular cross section of dimensions 18.8 mm × 3.2 mm (0.7402 in. × 0.1260 in.) has the stress-strain behavior shown in the Figure. If this specimen is subjected to a tensile force of 108900 N (24480 lbf) then
(a) Determine the amount of elastic strain...
Homework Statement
a tightly wound circular coil has 36.8 turns, each of radius .1m. the uniform magnetic field is in a direction perpendicular to the plane of the coil. the field increased linearly from 0 to .42t in a time of .251s.
what is the emf induced in the windings of the coil...
Homework Statement
A 1.60 cm x 1.60 cm square loop of wire with resistance 1.10 \times 10^{-2} \Omega is parallel to a long straight wire. The near edge of the loop is 1.10 cm from the wire. The current in the wire is increasing at the rate of 100 A/s
Homework Equations
I think I have...
Homework Statement
A solid conductor travels at 150 m/s across a uniform .045T magnetic field. Which side is positively charged and what is the emf across this block?
Homework Equations
I actually solved for the emf no problem. I am having difficulty determining which side is...
Homework Statement
http://img268.imageshack.us/img268/6536/physics1.png
Homework Equations
Lorentz Force = F = q(E+(v\times B))
The Attempt at a Solution
i. I = \frac{dQ}{dt}
So, dQ = number of electrons x area dx
i.e. I = \frac{n e d^2}{dt}dx = n e d^2 v_d
ii
Presumably the velocity...
Homework Statement
calculate total induced charge on a charged cylinder. where the surface charge density is given by sigma= 2eEo cos(phi)
Homework Equations
the total induced charge on the cylinder is
Integral of (sigma) da
can u calculate this integral fo me ... it very...
Homework Statement
1. Oersted discovered that a curernt carrying wire caused a magnet to move. Why does the magnet move?
2. Ampere discovered that a magnet caused a current carrying wire to move. Why does the wire move?
Homework Equations
(i) ∫Edl = - dΦ_B/dt
(ii) ∫Bdl = Iμ_0 +...
Homework Statement
A current is induced in a loop by something happening with current in a long straight wire near the loop. What could be happening? (There are two possibilities. Neither the wire nor the loop is moving.)
Homework Equations
Ampere's Law
Faraday's Law
The Attempt...
Please see question at . . . . http://www.flickr.com/photos/37144556@N07/3476115300/sizes/o/
(i) I am not sure which hand rule to use??
I think its the right hand rule, so does that mean the answer to question (i) is clockwise.
(ii) is the answer " in a circluar direction perpendicular...
Homework Statement
Please look into the attached file. In that you can see a block conductor is moving within the magnetic field which is acting isto the page. What will be the separation of the induced charge? will it be 1 or 2?
Homework Equations
The Attempt at a Solution
By...
Faraday's law says
induced emf = - d(flux)/dt
If this is applied to a loop where induced emf causes currents, and thus flux itself, do we have to consider that flux (of course we don't if it's constant)?
If the external flux has a nonzero second derivative, then the induced emf is...
Homework Statement
A loop of wire is situation between a wire (Wire 1) that is perpendicular to the loop and another wire (Wire 2) that is parallel to the loop (the diagram has the loop and Wire 2 in the plane of the page, Wire 1 is running "through" the page). Is a current induced, and in...
Homework Statement
Two insulated metal spheres of equal sizes are given equal positive
charges. The two spheres are brought very close to each other without
touching. Draw the new charge distribution on the spheres if one sphere
is much larger than the other.
Homework Equations...
Two straight conducting rails form a right angle where their ends are joined. A conducting bar in contact with the rails starts at the vertex at time t = 0 and moves with a constant velocity of 7.00 m/s along them, as shown in Fig 31-44. A magnetic field with B = 0.350 T is directed out of the...
Homework Statement
The rectangular loop shown has resistance 20.0 mΩ.
Determine the induced current in the loop at the instant shown.
Answer: 66.7µA
http://img264.imageshack.us/img264/7386/picture1nlz.png
Homework Equations
induced emf = |d(flux)/dt|
I = emf / R
The...
Homework Statement
Two coils are suspended around a central axis as shown in the figure below. One coil is connected to a resistor with ends labeled a and b. The other coil is connected to a battery E The coils are moving relative to each other as indicated by the velocity vectors v. Use...
What is the difference between "induced" and "influenced" ?
Hi
I don't understand , is it a different word for same phenomena ?
I'm novice to physics.
Thanks
Does anyone know of any really good resources on high turbulant flow/velocity induced vibration in piping systems (in particular this is a very high flow PSV off of a large vessel and they are concerned with dramatic pipe vibration when it relives) also it would be nice if the recommended...
Homework Statement
Homework Equations
l = 0.02 m
r = 0.3 m
E = \frac{-d\phi}{dt}
\phi = BA
The Attempt at a Solution
A = \pi 0.32^2 - \pi 0.3^2 = 0.0124\pi ...Area "cut" by conductor
\phi = 1.5a_r0.0124\pi = 0.0186\pi a_r ...change in flux in one revolution
1600...
Homework Statement A current loop with area A is placed in region II in the x-z plane, centered at the origin. (Below is a view looking down from y > 0.)
If the magnitude of the current per unit length in each sheet is increased (the directions stay the same), the induced current in the loop...
O.K, please let me see if I got it right:
Let M be an orientable m-manifold with non-empty boundary B.
Let p be a point in B , and let {del/delX^1,...,del/delX^(m-1) }_p
be a basis for T_pB for every p in a boundary component .
Let N be a unit normal field on B . Now, this is the...
In the double slit experiment, and observer such as a photon can hit an electron and thereby interact with. ie, a photon either hits an electron, or it doesn't. In this case, the photon hitting an electron induces decoherence.
If we make a similar analogy with water, ie. a water molecule...
Homework Statement
http://img27.imageshack.us/img27/1695/asdfgv.th.png
Homework Equations
Your guess is as good as mine
The Attempt at a Solution
I have no idea how to even begin this problem. What equations are relevant?
Homework Statement
A 800-turn solenoid, 18 cm long, has a diameter of 2.9 cm. A 15-turn coil is wound tightly around the center of the solenoid.
If the current in the solenoid increases uniformly from 0 to 3.1 A in 0.28 s, what will be the induced emf in the short coil during this time...
I am trying to conduct an investigation based on the set up of a set of copper coils with AC ran through them to make them an electromagnet. Held above them inplace is an aluminium plate. I know that the changing magnetic field induces a current in the aluminium plate, which induces a voltage...
Homework Statement
A long straight wire lies below to a circuluar loop of wire. The straight wire is carrying a constant 10A current to the right. What is the magnitude and direction of the current in the circular loop, if its diameter is 1 m and its center is 0.75m away from the wire...
Homework Statement
The drawing below shows a circular loop of wire (raadius 0.15m) connected to a power supply. The top loop is directly over the bottom loop, which is not connected to anything.
In the picture, the loops are shown parallel with one over the other, with the perspective...
Homework Statement
The drawing shows a bar magnet falling through a metal ring. In part a the ring is solid all the way around, but in part b it has been cut through. (a) Explain why the motion of the magnet in part a is retarded when the magnet is above the ring and below the ring as well...
Homework Statement
Resistance = R
Radius = r
Angle = theta
B = 2cos(2t)
Circular wire loop where magnetic field acts at theta degrees with respect to the normal of the wire loop.
Find induced current and emf in wire loop. Find induced electric field at radial distance d from center of wire...
Homework Statement
Resistance = R
Radius = r
Angle = theta
B = 2cos(2t)
Circular wire loop where magnetic field acts at theta degrees with respect to the normal of the wire loop.
Find induced current and emf in wire loop. Find induced electric field at radial distance d from center of wire...
(As magnitudes)
Faraday's law states that induced emf in a conducting loop by a changing flux, say x, is:
emf = dx/dt
Now if we have a circuit with the loop in series with wires (which are then tied together), how do I picture the voltages/currents in this circuit?
I mean, the actual...
I have a circuit set up like so: All in series, induction coils with internal resistance 22 ohms, attached to a resistor of 40 ohms.
When AC current is induced in the coils at a certain rate, the voltage dropped across the resistor is .14 V AC. The current, which should be the same...
I'm doing some experiments, and I need to measure the current (and/or voltage) going through several loops of wire as a magnet slides through. The magnet slides parallel under the loops at a certain speed. I have a multimeter and an ammeter. The problem with the ammeter is that it's just a...
Homework Statement
A circular loop made from a flexible, conducting wire is shrinking. Its radius as a function of time is . The loop is perpendicular to a steady, uniform magnetic field B .
Find an expression for the induced ε in the loop at time t.
Give your answer in terms of , , t, B and...
Homework Statement
A WxH rectangular loop of wire, with resistance R, lies on a table a distance s from a separate long straight wire carrying a current I.
If the loop is pulled to the right, parallel to the wire, with the speed v, then what is the magnitude of the current induced on the...
I would like to quantify the EMI on a circuit and I am confused on how to do that. I have two parallel wires that are laying on top of each other. I have tried to calculate the flux linkage and came up with:
\Lambda = [l*\muo*I/(2pi)]*ln((d-a)/a)
where a=radius of each wire...
The rectangular loop in the figure has 1.7×10^−2 ohm resistance. What is the induced at this instant? See picture below. Answer is in terms of I, like 5*I.
emf = Bvl
I= emf/R
B= [\mu_0 / 2*pi] *I * ln(.03/.02) since the magnetic field goes through the loop from 2cm to 3cm
then I used...
A parallel-plate capacitor, C=5 mircoF, has closely spaced circular plates of radius R = .1m.
How much displacement current is encircled in a loop of r=.05m that is centered on the axis between the plates when a uniform electric field between these plates changes with time at the rate of...
A time-dependent magnetic field inside a superconducting solenoid is directed perpendicular to its circular section. This magnetic field is confined to a cylindrical volume of radius .05m such that the magnetic field, B = 0 for radial distances r > R. Find the rate of change of the magnetic...
Homework Statement
Find the surface charge induced on an infinite conducting plate by a point charge +q at a distance a from the plate.
The Attempt at a Solution
As you probably know, this problem can be solved using the well-known fact that the induced electric field is equivalent to...
Homework Statement
This is part of a lab I did, I am working on the writeup now. We placed a coil of wire inside of a Helmholtz pair, with 20V of 60Hz AC through the Helmholtz pair. The coil inside was connected to an oscilloscope and the induced voltages were recorded. I now need to...
OK, so we have a stick 91cm long which is accelerated by 1m/s/s in a magnetic field B= 0.606T.
I need to find the induced voltage at time t = 288ms.
So U = B/V which is B/(a*t)
When i calculate i get 2 Volts which i think is too much. Plus the solution should be given in mV. Is this the...
Homework Statement
A two-loop wire circuit is 53.4069 cm wide
and 35.6046 cm high. The wire circuit in
the figure is located in a magnetic field whose
magnitude varies with time according to the
expression B = (0.001 T/s) t and its direction
is out of the page.
Assume The resistance per...
Homework Statement
A coil with 170 turns, a radius of 5.0 cm, and a resistance of 12 ohms surrounds a solenoid with 230 turns/cm and a radius of 4.7 cm; see the figure. The current in the solenoid changes at a constant rate from 0 to 1.8 A in 0.11 s.
Calculate the magnitude and direction of...
Homework Statement
A 32 turn circular coil of radius 4.60 cm and resistance 1.00 is placed in a magnetic field directed perpendicular to the plane of the coil. The magnitude of the magnetic field varies in time according to the expression B = 0.0100t + 0.0400t2, where t is in seconds and B is...