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# Flux & Flux Density

### electric flux of a hemisphere

Let..... be the closed surface that consists of the hemisphere and its base Let be the electric field defined by . Find the electric flux across . Write the integral over the hemisphere using spherical coordinates, and use the outward pointing normal. Please see the attached file for the fully formatted problems.

### Flux of Vector Field Across a Surface

Let S be the part of the plane which lies in the first octant, oriented upward. Find the flux of the vector field across the surface S. Please see the attached file for the fully formatted problems.

### 14 Modern Physics Questions

See attached file for full problem description. 1. A certain string on a piano is tuned to produce middle C (f = 261.63 Hz) by carefully adjusting the tension is the string. For a fixed wavelength, what is the frequency when this tension is doubled? a. 130.08 Hz b. 185.00 Hz c. 370.00 Hz d. 446.63 Hz e. 523.26 Hz 2

### Hail bounces off the roof of the car with a velocity of +15 m/s. Ignoring the weight of the hailstones, what is the force exerted by the hail on the roof.

Hail bounces off the roof of the car with a velocity of +15 m/s. Ignoring the weight of the hailstones, what is the force exerted by the hail on the roof.

### A loop of wire in a shape of a rectangular of width w and length L and a long, straight wire carrying a current I lie on a tabletop. Determine the magnetic flux through the loop due to the current I.

A loop of wire in a shape of a rectangular of width w and length L and a long, straight wire carrying a current I lie on a tabletop. Determine the magnetic flux through the loop due to the current I. See attached file for full problem description.

### Magnetic Flux and Magentic Field

See attached file for full problem description. 1. Two circular coils of radius R each perpendicular to a common axis. The coil centers are a distance R apart and each coil carries a steady current I in the same direction. Show that magnetic field on the axis at a distance x from the center of one coil is Show that are bot

### Physics questions on oscillations and waves

1. A certain string on a piano is tuned to produce middle C (f = 261.63 Hz) by carefully adjusting the tension is the string. For a fixed wavelength, what is the frequency when this tension is doubled? a. 130.08 Hz b. 185.00 Hz c. 370.00 Hz d. 446.63 Hz e. 523.26 Hz 2. A bell is ringing inside of a sealed glass jar

### To determine the equivalent winding resistance, percentage regulation, efficiency of a single phase transformer.

A single-phase transformer is rated 100kVA, 2200:440 volts. When carrying rated current with the low voltage terminals short-circuited, the input power was 1.14kW, and the applied voltage 93V rms. (a) Determine the equivalent winding resistance and leakage reactance of the transformer referred to the low voltage side. (b)

### Magnetic Circuits: MMF and Reluctance

The magnetic circuit shown in figure below is built up of solid iron cross section, 1x1cm2. Each air gap is 1 mm wide. For this type of air gap, the effective cross-section of the air may be taken as 1.2 x that of iron path to allow for fringing. Two different grades of iron are used. When a coil having 2000 turns is wound on pa

### 4 Electrostatics Problems: Field, force, potential, energy

(See attached file for full problem description) --- A small plastic ball of mass 6.39 x 10-3 kg and charge +0.164 C is suspended from an insulating thread and hangs between the plates of a capacitor (see the drawing). The ball is in equilibrium, with the thread making an angle of 30.0° with respect to the vertical. The ar

### Electrostatics: Unequal Charge density on parallel plates

(See attached file for full problem description) --- 1. Consider two infinite parallel plane conducting plates, of finite thickness, with separation d. Suppose a charge density of sigma; is placed on one plate, while the other plate has -2sigma. A) Determine the resulting charge densities on each of the 4 surfaces B) De

### Air speed at nozzle exit

Air is flowing through a rocket nozzle. Inside the rocket the air has a density of 5.25 kg/m cubed and a speed of 1.20 m/s. The interior diameter of the rocket is 15.0 cm. At the nozzle exit, the diameter is 2.50 cm and the density is 1.29 kg/m cubed. What is the speed of the air when it leaves the nozzle?

### You have a neutron with a kerma of some amount. How do you calculate the fluence?

You have a neutron with a kerma of some amount. How do you calculate the fluence?

### Current in a Loop

If the current in the loop of the attachment were halved, the total flux threading the loop would: 1) Halve 2) Be reduced to 1/4 of the previous value 3) Decrease to 3/4 of its original value 4) Decrease by more than 1/2 but greater than 1/4 its previous value.

### Static Magnetic Field Theory

Q1) What is the flux density of the current loop in the plane of the loop on the attachment? 1) 1.68 x 10^ -5Wb/m^2 2) 2.36 x 10^ -5 Wb/m^2 3) 1.68 x 10^ -4 Wb/m^2 4) 2.36 x 10^ -4 wb/m^2 5) 2.87 x 10 wb/m^2 6) None of the above Q2) What is the value of the total flux threading the loop? 1) 5.92 x 10^ -8wb

### Static Magnetic Field - Flux, direction of flux, equivalent reluctance of the core, permeability of the core material

See the attached files. In the attachment titled "Box Question" are questions for the second attachment, titled "The Box", a diagram.

### What change in magnetizing force is required to decrease the flux density of magnetic material

A) What change in magnetizing force is required to decrease the flux density of magnetic material from a saturation in the positive direction to zero. B) Also same question, however magnetic force is required to reverse the direction of the magnetic field from saturation in the positive direction in the direction to saturatio

### Manufacturing Process for Making Steel

Please give a brief description on how steel is made that addresses the following: - What process is used (i.e. product focus, process focus or group technology/cellular manufacturing - Anything surprising in the process - Is there anything that is particularly interesting or creative about the process - How might this pr

### Strategic management

The managers of a company are deciding whether to develop a brand new product not yet seen in the marketplace or a version of a competitor's product that has already been launched in the marketplace. 1. Management want to know if they should follow the "first-mover" or "late-mover theory 2. develop a presentation that wil

### Find the flux of the vector field.

Let S be the part of the plane 2x + y + z = 1 which lies in the first octant, oriented upward. Find the flux of the vector field F = 3i + 3j + 3k across the surface S.

### Electric Flux Through a Gaussian Spehere

A point charge produces an electric flux of +545 Nm^2/C through a Gaussian sphere of radius 17.0 cm centered on the charge. (a) What is the flux through a Gaussian sphere with a radius 34.0 cm? (b) What is the magnitude and sign of the charge?

### Heat Flux Calculation: Copper Wire

Please see the attached file for the fully formatted problem(s). 1. A heated copper wire 1 mm in diameter is in a pool of water at 1 atm. What is the maximum heat flux (q/A)? The temperature difference is related to the heat flux (q/A) by the following equation: [Equation] What temperature difference (which we'll cal

### Activity and activation cross section.

A cobalt foil, 1 cm diameter x 0.1 mm thick, is irradiated in a mean thermal flux of 10^11 n/cm^2-s for a period of 7 days. If the activation cross section is 36 barns and if the density of cobalt is 8.9 g/cm^3, what is the activity (Bq) at the end of the irradiation period?

### DC Series Motor Question

When operating from a 230 V dc supply, a DC series motor operates at 900 rounds per minute with a line current of 75 Amps. Its armature-circuit resistance is 0.13 Ohms, and its series-field resistance is 0.09 Ohms. Due to saturation effects, the flux at an armature current of 25A is 45 percent of that at an armature current of

### Beams of Monoenergetic Neutrons

Two beams of monoenergetic neutrons with energy equal 1eV intersect at an angle of 90 degrees. The density of neutrons in both beams is 2x10^8n/cm3. a) Calculate the intensity (current) of each beam. b) Calculate the neutron flux where the two beams intersect. c) Calculate the neutron current where the two beams intersect.

### Flux and Current

Consider a point source emitting 10^12 neutrons/s in a vacuum. Calculate the flux and the current at a distance of 1 m from the source.

### Flux of Space Regions Bounded

Consider the space region bounded below by the right angled cone z=sqrt(x^2+y^2), and above by the sphere x^2+y^2+z^2=2. These two surfaces intersect in a horizontal circle, let T be the horizontal disk having this circle as boundary, S the spherical cap forming the upper surface, and U the cone forming the lower surface.

### Electrical Energy Conversion: Voltages & Currents

Question: Find the current I_N, required to establish a flux of 2 mWb in the air gap of the magnetic structure shown in the figure in the attached file. The structure is made of silicon sheet steel, and its magnetization curve is also shown. Assume that the coil has 500 turns, and the structure has the dimensions given in the at

### Solenoid Magnetic Field, Flux, and Inductance

A 40.0-mA current is carried by a uniformly wound air-core solenoid with 450 turns, a 15.0-mm diameter, and 12.0-cm length. Compute (a) the magnetic field inside the solenoid, (b) the magnetic flux through each turn, and (c) the inductance of the solenoid. (d) What if the current were different? Which of these quantities wou

### Physics - Electric Flux

A charge of 170 micro coulomb is at the center of a cube of edge 80.0 cm. a)Find the total flux through each face of the cube. b)Find the flux through the whole surface of the cube. c)What if ? Would your answers to part a or b change if the charge were not at the center? Explain.