Diameter Definition and 508 Threads

Homework Statement The problem is attached in the picture. The Attempt at a Solution I managed to solve it using a different method. I have no idea what the answer is talking about.. My method Found dI of a strip = (1/3)*dm*h2 then i replace h by x, then integrate from -a to...

Homework Statement A small light is 22.0 cm below the surface of a liquid of refractive index 1.50. Viewed from above, the light appears to illuminate a circle on the surface of the water. What is the diameter of the circle? cm Homework Equations Snell's Law n1sin(θ)1 = n2sin(θ)2...

Trying to understand what will happen to the fluid in the following scenario. Lets say there is a length of pipe with an OD of 4", what would happen if halfway along the pipe the pipe OD increased to 6" (gradual increase). I believe the pressure of the fluid will decrease, would the flow...

Homework Statement A projection aligner has an object to lens distance of 500mm. Calculate lens diameter for the aligner if NA = 0.28. Assume the usable area of lens is 90% of its diameter.Homework Equations NA = r / D Note: NA is the numerical aperture. The Attempt at a Solution I know that...

Most of the applications requiring small diameter laser spots are generated by focusing of laser light and that has a theoretical diffraction limited minimum diameter equal to the wavelength. Does anyone know what is the smallest fully collimated beam (small divergence say single digit milli...

Volume of a sphere: \frac{4}{3}\pi r^{3} Volume of a sphere in terms of diameter: \frac{\pi d^{3}}{6} Rate of volume: \frac{d}{d(time)}volume = -1 cm^{3}/min. Rate of diameter: \frac{d}{d(time)}10 cm = ? I'm not sure what to do at this point

The left end of a long glass rod 6.00cm in diameter has a convex hemispherical surface 3.00cm in radius. The refractive index of the glass is 1.60. Distances are measured from the vertex of the hemispherical surface. A.)Determine the position of the image if an object is placed in air on the...

hello! lets say we have a long tube with variable diameter and with variable direction is it possible to measure the diameter of its walls in each point of its lenght, by sending waves or something from its edge towards inside it ? imagine it is not possible to access the outside of the...

hello! I am interested to know if a tube can be created that with some kind of mechanism, its diameter will increase on demand the range of the diameter should start at the smallest possible (0.01 mm or less if possible, even if the walls of the tube virtually concur) and increase up to...

Hi guys i have a exam coming up soon and stress is starting to kick in. I am good withy stress and strain, but just confused on this two questions and don't understand what I am doing wrong. I've tried every formula and i just can't seem to get question 6 out. And question 5 same problem i...

in a chunk of a pure element like iron-would the outside diameter of the the last electron shell ever naturally change from picosecond to picosecond?

Homework Statement Given in uploaded file Homework Equations σallow=\frac{P}{A} τallow=\frac{V}{A} The Attempt at a Solution Given in uploaded file Answers are d=16mm, h=10mm I tried using methods used in previous questions but it didn't work out for me here, if anyone could...

Homework Statement If it takes 17 seconds to blow up a balloon to 8 cm in diameter, how much longer will it take to inflate the balloon to 24 cm in diameter? Assume that the pressure that the balloon exerts on the air inside is proportional to the surface area of the balloon, that you blow...

OK, I'm designing an Open Source Kite Ring Generator. See kitepowercoop.org for details. I have designed a system which uses a large inflated torus with kites attached radially around the axis on which it spins. I believe that removing the inside hub of a standard wind turbine by working in...

I am a bit of confused with the following terms involved in the study of lenses: Diameter of lens Aperture of Lens Are these terms synonomous? And how are they related to focal length of a lens?

Hello all, First time here and first time posting. Just like to say a quick hello before getting started... Due to the rise of solar PV panels being installed before the Feed in Tariff was cut earlier this year (in the UK) I've been thinking about the cable losses that these incur...

Hello all, Just trying to find a formula and need some help. If a tire is 22 inches in diameter, what are the RPMs of the outer diameter of a 22 inch tire versus the RPMs of the outer diameter of a 2.5 inch center cap, on a car traveling 30 MPH? Are they the same, or are the rotations of the...

Homework Statement I'm reading a worked problem in my "Fundamentals-of-Physics" textbook, and it states Homework Equations The Attempt at a Solution I was wondering what are the molecular diameter units which I have emboldened? What does pm stand for? Thank you

Homework Statement Derive the moment of inertia of a solid, uniform density, disk rotating about a diameter using vertical rods. Diagram: http://i.imgur.com/TQIjz.png Only the radius of the circle and the inertia of a thin rod is given Homework Equations Inertia of thin vertical rod = m*r^2...

My zipline is 200 feet long built with 7/16" Stainless Steel Cable. Would 3/8" cable result in a faster ride with less noise from the trolley due to significantly less surface area for friction?

Homework Statement In an examination of a certain element using the Debye-Scherrer technique the following diffraction angles (in degrees) were noted: 45.26/65.92/83.56/100.6/118.68/140.88 Radiation λ=0.1540 nm was used. Obtain two estimates of the atomic diameter of the element in...

can anyone tell me how the orifice diameter can affect the vortex forming ? no much info from internet , thanks for help~:smile:

Explain why the diameter of almost every complement of a tree will be 2 and find all exceptions to this rule

Homework Statement Imagine viewing an eclipse of Charon by Pluto. Assume the satellite orbit is nearly circular, of known radius a, and is viewed edge-on. Explain how you could use the observations to infer a diameter for Pluto Homework Equations Orbital radius R=a The Attempt at a...

Hi, We are using a radio interferometer to measure the angular diameter of the Sun. An in depth description of how this is done is not relevant to solve the immediate problem I have. But briefly, we rotate the interferometer in azimuth so that the direction it's looking at traverses across...

Homework Statement Show that open ball B(0,r) \subset \mathbb{R}^2 has a diameter 2r. The Attempt at a Solution Intuitively i'd say right away that it can't be 2r but i presume it has to be since I'm being asked to prove it. To simplify the situation, i'll think about this in one...

Homework Statement A bicycle with tires 70 cm in diameter is traveling along a road at 25 km/hr. What is the angular velocity in radians per second? (the answer given in the textbook is 19.8 radians per second) Homework Equations A= 1/2r^2 ∅ l = (radius)(central angle)The Attempt at a Solution...

Homework Statement Two parallel plates are placed 0.10 m apart with one vertically above the other and their edges aligned. The potential difference of the upper plate is 100 kV relative to the lower plate. What charge must a spherical raindrop of diameter 1.0 mm carry if it remains...

Homework Statement I have a question where I'm given the voltage, mass, resistivity, and density of a wire and I need to find the diameter and the length. Can someone show me how to do both of these? Homework Equations I have no idea what equation would relate voltage, mass...

How big would the nucleus be? A grain of sand (0.1cm diameter) A marble (1cm diameter) It's a grain of sand right(?); since the relationship between the diameter of an atom and its nucleus is 100,000 to 1. 150/0.001= 150,000

Hello, I am a firearms enthusiast. In my collection is a Gewehr 88/05. This was Germany's first smokeless issue rifle and it originally used a smaller bore than is used today in the 8mm. It was converted in 1905 to take a 0.323" bullet instead of a 0.318" bullet. The leade (free...

hi guys, m a lil stuck here what voltage would be rquired to heat a 7cm long copper wire of .75mm diameter in about 2-3 seconds.the target temp is 400-450c. dr ankit

A balloon is made from material that has a density of 0.310 kg/m2. If the balloon has a mass of 2756 kg and if it is assumed that the balloon is a perfect sphere, what is the diameter of the balloon? Keep the proper number of significant digits. Mass = Density x Volume 2756kg = 0.310kg/m^2...

Homework Statement suppose that a metric space A is a union A = B U C of two subsets of finite diameter. Prove A has finite diameter. Homework Equations The Diameter of a metric space M is sup D(a,b) for all a,b in M. The Attempt at a Solution Really, no idea where to begin. I just...

Homework Statement Hi, i need some help with this question, A string of length 60cm and diameter 0.80 mm is under tension 64 N. When plucked, it emits a frequency of 660Hz. What is the new frequency if the length is decreased to 40cm, the diameter decreased to 0.50mm and the tension increased...

Homework Statement If we know, that 200 mm of tungsten wire weight`s 1.72 mg, then what is the diameter of this wire Homework Equations The Attempt at a Solution I by my self came to the conclusion, that the answer is 0.13 mm. But if I take in accordance, that my Algebra and...

Homework Statement A 2cm diameter cylindrical solenoid of 10 loops and 20cm long is in a perpendicular magnetic field of 0.7Tesla directed away from you. The field increases to 2.7Tesla in 100ms. The loop has 8Ω. What is the EMF? What is the current? What is the magnetic field of the...

Homework Statement A scuba diver releases an air bubble of diameter 1.0 cm at a depth of 15 m below the surface of a lake. What will be the diameter of this bubble when it reaches the surface? Assume that the temperature of this bubble remains constant. Homework Equations p=F/A...

Homework Statement A scuba diver releases an air bubble of diameter 1.0 cm at a depth of 15 m below the surface of a lake. What will be the diameter of this bubble when it reaches the surface? Assume that the temperature of the bubble remains constant. Homework Equations The...

A mild stell bar 40 mm diameter and 100 mm long is subjected to a tensile force along its axis. Young's modulus of elasticity = 200 GN m -2. Poisson's ratio is 0.3. Calculate the force required to reduce the diameter to 39.99 mm It says use the x-y coordinate system?? This i don't...

Homework Statement Cosmologists have speculated that black holes the size of a proton could have formed during the early days of the Big Bang when the universe began. If we take the diameter of a proton to be 1.0*10^{-15}, what would be the mass of a mini black hole?Homework Equations...

I need to find the volume of air (ft^3) for this sample. The air is discharged at 40 psi for 1 minute and the diameter of the pipe is 0.5 inches (Area = 0.001363538 ft^2). I think I need to solve for the velocity of the air (vel = sqrt(2P/rho), where P is the pressure and rho is the density)...

Homework Statement Like the title says, I have a homework problem that asks for the maximum diameter of a hole that can be punched into a sheet of polystryrene 6 mm thick, knowing that the force exerted by the punch is 45 kN and that a 55 MPa average shearing stress is required to cause the...

Homework Statement What diameter should the nichrome wire in the figure be in order for the electric field strength to be the same in both wires? Homework Equations σ = 1/ρ J = σ*E...I/A = σ*E...I = σ*E*A Then, equate the current equations for each wire. The Attempt at a...

Homework Statement For what electric field strength would the current in a 2.0 mm diameter nichrome wire be the same as the current in a 1.0 mm diameter aluminum wire in which the electric field strength is 0.0080 V/m? aluminum diameter = 1.0 mm Same current(I) flowing through both wires...

Hi Is there a way of transposing the formula to calculate the width (W) from a known height (H) and hydraulic diameter (Dh)? Dh = (2xWxH)/(W+H) Many thanks Jon

Hey all, I have been mulling this around in my head for awhile and cannot make sense logically. In thinking about a sphere falling through some random liquid, how does decreasing the diameter of the sphere affect the rate at which it falls? I am thinking of two formulas and the seem to...

We cannot measure the diameter of Earth inch by inch using rulers, and must somehow estimate the distance on Earth, Does anyone have any suggestions on what approach they use to measure the diameter of Earth? and how does this approach apply to measure the diameter of other planets? Thanks in...

The manual lathe I work on has a degree scale for the arm. I have the radiuses in mm and the diameters in mm of two zones I have to cut. What formula can I use to determine the angle which delimits the two zones? For example: Say I have an item 15mm in diameter. Inner zone A is to have a...

Let A be a subset of a metric space such that A ⊆ B (p, r) for some p ∈ X and r > 0. Show that diam(A) ≤ 2r. B(p,r)=(p-r,p+r) diam( B(p,r) )=sup{d(a,b)│a,b∈B(p,r) }=d(p-r,p+r)= 2r Since A ⊆ B (p, r), the diameter of A is less than the diameter of B (p, r): diam(A)≤2r Is it true and enough? I...