Questions
how fo wind turbines effect the community? (aesthetics, noise, and environmental considerations)

how fo wind turbines effect the community? (aesthetics, noise, and environmental considerations)

In: Physics

(day 42) Dr. Aloysius found four homogeneous mixtures, but he thinks that only three are alloys....

(day 42)
Dr. Aloysius found four homogeneous mixtures, but he thinks that only three are alloys. He tests each ine and determines their elemental compositions. which of the following is not a possible alloy

1.) iron, carbon, and nickel
2.) aluminum, and magnesium
3.) iron and nickel
4.) carbon and boron

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An electric dipole is formed from 1.2 nC charges spaced 2.4 mm apart. The dipole is...

An electric dipole is formed from 1.2 nC charges spaced 2.4 mm apart. The dipole is at the origin, oriented along the y-axis. What is the electric field strength at the following points?

(a) (x, y) = (10 cm, 0 cm)

______N/C

(b) (x, y) = (0 cm, 10 cm)

_____N/C

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A m1 = 1.00-kg aluminum block and a m2 = 6.10-kg copper block are connected by...

A m1 = 1.00-kg aluminum block and a m2 = 6.10-kg copper block are connected by a light string over a frictionless pulley. The two blocks are allowed to move on a fixed steel block wedge (of angle θ = 34.5°) as shown in the figure. (For aluminum on steel, μs = 0.61 and μk = 0.47. For copper on steel, μs = 0.53 and μk = 0.36.) (a) the acceleration of the two blocks and (b) the tension in the string

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You are holding a shopping basket at the grocery store with a 1.24-kg carton of cereal...

You are holding a shopping basket at the grocery store with a 1.24-kg carton of cereal at the left end of the basket. The basket is 0.61 m long. Where should you place a 1.9-kg

gallon of milk, relative to the left end of the basket, so that the center of mass of your groceries is at the center of the basket?

Hello ! I'm studying for a test tomorrow and looking for steps on how to do this.

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A spherical shell has in inner radius Ri and an outer radius Ro. Within the shell,...

A spherical shell has in inner radius Ri and an outer radius Ro. Within the shell, a total charge Q is uniformly distributed.

Calculate:

a) the charge density within the shell (if you cannot get this answer, you can proceed without it).

b) the electric field strength E(r) outside the shell (r > Ro).

c) the electric field strength inside the shell (r< Ri).

d) the electric field within the shell (Ri < r < Ro)

e) show that your solutions match both inner and outer boundaries

f) Draw a graph E versus r.

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Cosmic acceleration and dark energy Q: How do we measure the changes in the expansion rate?...

Cosmic acceleration and dark energy

Q: How do we measure the changes in the expansion rate?

Q: What is a standard candle? Why are supernovae useful as standard candles?

Q: What is so bizarre about the universe accelerating? What are the possible explanations for this? Which solution is the least radical?

Q: Why is dark energy invoked to explain the accelerated expansion?

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The maximum distance from the Earth to the Sun (at aphelion) is 1.521 1011 m, and...

The maximum distance from the Earth to the Sun (at aphelion) is 1.521 1011 m, and the distance of closest approach (at perihelion) is 1.471 1011 m. The Earth's orbital speed at perihelion is 3.027 104 m/s. Ignore the effect of the Moon and other planets. (a) Determine the Earth's orbital speed at aphelion. m/s (b) Determine the kinetic and potential energies of the Earth

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C) A 0.315 kg bird flying along at 6.5 m/s sees a 0.019 kg insect heading...

C) A 0.315 kg bird flying along at 6.5 m/s sees a 0.019 kg insect heading straight toward it with a speed of 23 m/s (as measured by an observer on the ground, not by the bird). The bird opens its mouth wide and enjoys a nice lunch. What is the bird's speed immediately after swallowing the insect? Answer in m/s

D) A 2.6 kg block slides along a frictionless surface at 1 m/s. A second block, sliding at a faster 5.9 m/s, collides with the first from behind and sticks to it. The final velocity of the combined blocks is 2.9 m/s. What was the mass of the second block? Answer in kg

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An airplane is dropping an aid package in a remote area. The plane is moving horizontally...

An airplane is dropping an aid package in a remote area. The plane is moving horizontally at speed v0 and the package lands a horizontal distance L from where it was released by the plane. a) Find the time it takes for the package to land. b) Find the altitude of the plane. c) Find the velocity (vector) of the package when it lands. d) Find the speed of the package when it lands. Write your results in terms of v0, L, and g. Check the units/dimensions for each answer.

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Describe the difference between photoablation and plasma-induced ablation. Discuss the advantages and disadvantages of these interaction...

Describe the difference between photoablation and plasma-induced ablation. Discuss the advantages and disadvantages of these interaction mechanisms for refractive corneal surgery.

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A bullet with a mass m b = 13.1 g is fired into a block of...

A bullet with a mass m b = 13.1 g is fired into a block of wood at velocity v b = 245 m/s. The block is attached to a spring that has a spring constant k of 205 N/m. The block and bullet continue to move, compressing the spring by 35.0 cm before the whole system momentarily comes to a stop. Assuming that the surface on which the block is resting is frictionless, determine the mass of the wooden block.

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How does Newton's laws relate to uniform circular motion?

How does Newton's laws relate to uniform circular motion?

In: Physics

The picture below shows an isolated system with a fairly massive wheel at one end, attached...

The picture below shows an isolated system with a fairly massive wheel at one end, attached via its axle to a long shaft, like a bike tire on a bike frame, but the bike frame is merely a low mass 'truss.' At the other end of this long shaft is a mass of roughly the same magnitude as the wheel, so the center of gravity (CG) is roughly in the middle of the shaft. This mass is fixed to the shaft with no rotation possible. The assembly is floating motionless in 'space', with no contact to anything else.

Diagram of apparatus

If a motor on the 'truss' causes the wheel to spin in one direction, the truss would begin to spin in the other direction about the common center of mass. The net angular momentum would thus be zero both before and after the spinning commences. The wheel and the truss would rotate in the same plane. The actual rotation rate of each part is dependent upon the individual masses, wheel radius, and the length of the shaft. It is getting complex, but so far easy enough to envision in general.

Now, place into the 'truss' a mechanism that causes this long shaft to rotate on its long axis (which would be perpendicular to the spin axis) while it is still undergoing the above rotation relative to the wheel. Upon rotation at this new joint, a force is applied to the axle of the spinning wheel (and of course to the mass at the other end of the truss, too) causing each part to try to turn in the opposite direction. Given that the net angular momentum is still zero, the vector sum of the individual parts (the spinning wheel and the body as a whole rotating around its CG) must be equal and opposite. I cannot envision the result, however, nor do I have the background to derive the equations of motion of this 'whirly gig.' The best I can imagine is that the plane of overall rotation should change, with the plane of the wheel's rotation changing in the opposite direction. This would seem to result in a state where the wheel is no longer spinning in the same plane as the overall assembly, but that would seem unsustainable and perhaps unstable. How can the behavior of this system be understood?

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3. Two ice skaters collide on the ice. A 39.6-kg skater moving South at 6.21 m/s...

3. Two ice skaters collide on the ice. A 39.6-kg skater moving South at 6.21 m/s collides with a 52.1-kg skater

moving East at 4.33 m/s. The two skaters entangle and move together across the ice. Determine the magnitude

and direction of their post-collision velocity (answer: 3.64 m/s at 42.5 degrees)

Please provide a detailed diagram

In: Physics