Change in gas velocity and pressure entering and exiting a duct or pipe expansion section (diffuser). Looking for a formula to determine velocity, pressure and density of a gas as it exits a duct or pipe diffuser section based on the entrance area to exit area ratio. Ambient temperature...
What are your opinions on the discipline of Economics ? Do you think it has the potential to be used to help people or do you think it is simply a tool used by the rich and powerful.
Is Economics a science ? Is the mathematics behind it sound ?
I have friends who say it is fluff, that it...
Homework Statement
A Cadillac of mass 2250 kg going east collides with a Geo of mass 1180 kg headed north on a level highway. The cars remain tangled and slide to rest after traveling 25 m in a straight line at an angle of 20° north of east. The coefficient of kinetic friction for the tires on...
why does lowering the density change the trajectory?
why does lowering the density change the trajectory?
Is this a basic/general question or is more information needed??
totally lost...:confused:
Next quarter I'm taking 2 classes. About 8 quarter units. I need 12 to be full time. Would it look bad to grad schools if I'm not a full time student for one quarter?
Hi,
I was hoping someone might be able to help with some questions about composite toughness.
I am trying to find an FRP composite with comparable impact toughness and yield strength to 7075 T6 Aluminium. I'm having trouble finding any means of direct comparison. I've read that Kic is not...
Homework Statement
Prove that if the acceleration is constant, the average velocity=vf+vi/2
Homework Equations
average velocity=xf-xi/change in t
xf=xi+vit+1/2at^2
vf^2=vi^2+2a(xf-xi)
The Attempt at a Solution
I started out by drawing a diagram:
_ _ _ _ _ _ _ _ _
Vi...
Nader is running for President again. There is little chance that he will pull away much McCain support, but he could manage to hurt the Democratic nominee in an otherwise tight general election. McCain's got to be rubbing his hands together with a grin on his otherwise botoxed, frozen face...
Hello. I'm having the hardest time finding a product (preferably an IC) that can detect shock. Like if you dropped your phone on the ground it would detect an impact with the floor, with some kind of threshold to ignore minor bumps and thumps. I did find some toshiba ICs called "shock detector...
Help! Bullets And Impact Math!
Hi there. I will introduce myself as an aspiring mind. However though my study skills are well developed, my advanced math skill are sadly lacking . . .:smile:
Here is the thing, I have developed a passion for the study ballistics. And after sometime I have...
A freeze in southwestern U.S. and Mexican fields has resulted in damaged crops and inflated prices for imported produce such as lettuce, broccoli and cauliflower.
Describe how this would be interpreted on a supply and demand diagram. Do not draw graph.
*Please include one(if you can) so I...
Homework Statement
I am creating a device to provide 250 to 300 g's of impact force to an electrical device in a plastic housing. I would like to lift a steel plate approximately 16" x 16" X thickness "T",, to a height of "Y" and release it. It would fall at the rate of gravity, impacting a...
I was wondering if anybody could help me. I need to calculate the impact force exerted on an rov if it collides with a oil well tree. The information I have are the mass of the rov = 500 kg, initial velocity othe rov is 1.5 m/s and the oil well tree is a fixed body. I am unsure how to calculate...
To my knowledge, The Trouble with Physics...and What Comes Next is the only book on the market which not only criticizes the virtual string monopoly in the US but also describes a range of other QG approaches pursued abroad and blocked here. What interests me about Smolin's book is that it makes...
Homework Statement
A tennis ball has a mass of 0.057 kg. A professional tennis player hits the ball hard enough to give it a speed of 52 m/s (about 117 miles per hour.) The ball moves toward the left, hits a wall and bounces straight back to the right with almost the same speed (52 m/s). As...
Some earlier threads have been dedicated to the Younger Dryas and a possible connection to an impacter. Here is the full paper about it.
http://www.pnas.org/cgi/reprint/104/41/16016, Evidence for an extraterrestrial impact 12,900 years ago that contributed to the megafaunal extinctions and...
And would you do it if you had the chance? How soon would the Theory of Everything be discovered once this became possible? Days perhaps? What would the impact be if you had thousands of people who were 1 million times smarter than they were yesterday?
I'm currently in grade 12 physics. For my summative project in the class (which is worth a large part of my final mark) I have to think of three separate ways to divert a large asteroid away from hitting earth. We were each given a real object and stats on the object. My first problem is that...
[SOLVED] Arrow- Finding the point of impact
Homework Statement
An archer shoots an arrow horizontally parallel to the ground at a height of 1.5 m,
above the ground, aimed directly at the centre of a target marked on a vertical wood panel situated 30 m from the archer. The arrow is released...
You throw a ball with launch velocity of \overrightarrow {v_i}=(3m/s)\widehat{i}+(4m/s)\widehat{j} toward a wall, where it hits at height h_1} in time t_1 after the launch. Suppose that the launch velocity were, instead, \overrightarrow {v_i}=(5m/s)\widehat{i}+(4m/s)\widehat{j}.
Would the time...
Hi,
I'm trying to solve an argument and hope someone can point me in the right direction.
How does one calculate the impact force of a 7.26kg bowling ball traveling at 12 meters per second and impacting a single pin weighing 1.64kg. I calculated the energy of the bowling ball at 662 Newton...
If evolution is correct, might we be fairly certain than in many thousands of years, the new "intelligent species" on Earth will be an entirely different species, and humans will have long since gone extict?
The US has an extreme string monopoly situation compared with other countries (as several posters including f-h and John Baez have mentioned elsewhere) in the sense that there is only one non-string QG research group in the whole country.
This contrasts with Europe, Canada, not to mention other...
Homework Statement
A meteor of mass about 3.4 x 10^12 kg is heading straight for Jupiter. When it hits there will be a huge release of energy, visible her on earth. Assuming it has fallen from far away, how much energy will be released when it hits Jupiter? The radius of Jupiter is 7 x 10^7 m...
1. A sphere of mass m impinges obliquely on a sphere of mass M, which is at rest. The coefficient of restitution between the spheres is e. Show that if m=eM, the directions of motion after impact are at right angles
2. Coefficient of restitution -
3. I really don't think I have a...
Homework Statement
A body is fired vertically upwards with an initial velocity of 100m/s.
(a) how far will it rise
(b) how long will it take to reach maximum height?
(c) what is the time taken before it strikes the ground again.
(d) what is the velocity at impact
Homework Equations...
What nuclear fission reactor design has the least environmental impact? Including the building, operating, safety, and amount of pollution produced?
I'd imagine IFR/breeder reactors as they burn actinides.
Homework Statement
A bullet, having a mass of 18g and traveling with a velocity of 1200 m/s strikies a wooden block and pentrates 2.5m. What is the average force exerted by the block on the bullet?
Homework Equations
W= F*total distance
W= .5*m*V2^2 - .5*m*V1^2
The Attempt at a...
Homework Statement
During an autumn storm, a 0.012 kg hail stone traveling at 20 m/s made a .20 cm deep dent in the hood of a person's car. What average force did the car exert to stop the damaging hail stone?
Homework Equations
d = vt
ft = mv
The Attempt at a Solution
Vav =...
How much of a problem is to have a Phd advisor who hasn't published anything in area/field A for over a decade where A is the field I like to do the Phd in?
I have no clue how to do this problem, so if someone could explain to me step by step, it would be greatly appreciated!
<a href="http://photobucket.com" target="_blank"><img src="http://i231.photobucket.com/albums/ee10/mitochondria3/DavidGoliath.jpg" border="0" alt="Photo Sharing and...
Homework Statement
3. A 15MeV Alpha particle is incident at impact paramter b=0 on a Mg Nucleus, atomic number Z=12 and atomic mass A=24. What is the distance of closest approach?
Homework Equations
None given, but I thought the following might be relevant:
r_{min}=\frac{Zke^{2}}{KE}...
[SOLVED] Calculate Average Force by finding Impulse over Impact Time
Homework Statement
A movie depicting a 55-g golf ball hit with a club shows that the impulse time between the club and the ball is 0.2 ms, and the initial speed of the ball is 136 mph.
a) What is the average force exerted...
The US has an extreme string monopoly situation compared with other countries (as several posters including f-h and John Baez have mentioned elsewhere) in the sense that there is only one non-string QG research group in the whole country.
This contrasts with Europe, Canada, not to mention...
Hiya,
I have had to do an investigation on hookes law as part of my primary school teaching course. i am by far not the best at understanding physics. Can someone please explain to me what effect the width of a piece of elastic has on its elasticity and why?
thanks
Testing of Impact Sensor--Verify G-Force Readings
I'm thinking either free fall test or pendulum
but I was just curious if anyone could suggest an easier method
We are looking for a way to test a newly developed impact sensor and verify that we when it says it has been hit with 5 g's for...
[b]1. A mass is hitting the end of a hinged rod. After impact they begin to rotate.
The motion is then confined to a single plane. why? what plane?
[b]3. I am a bit confused by what they mean by a single plane. Are they saying that there are only x,y coordinates? Is this just a condition for...
gooooood evening..
i have presentation about the effect of vibration on human and i did not find what i want and i did not understant the topices when i searched from google .. so I will be grateful if anyone could help me..
Hi all I fly model planes in combat and need to build a wing that will withstand a head on impact! I am going to use epp foam to form the wing and a carbon spar
the foam will be cut at the spar line and the spar will be a H rotated 90deg so that the foam slots in either side
what I need to...
Homework Statement
Our homework set today was to find out why is it that when you hit someone at 30mph they have a 20% chance of dying. Yet when you hit someone at 40mph they have a 90% chance of dying.
Homework Equations
KE = 1/2 M V^2
The Attempt at a Solution
First of all i...
In 2006, the mathematically rigorous proof of the Poincaré conjecture was completely excepted. The Poincaré conjecture was put forward by Henri Poincaré in the early 1900's. It is a theorem about the characterization of the 3D sphere amongst 3D manifolds. It was considered one of the most...
A friends father told him that a hydroshock bullet (a type of hollowpoint bullet that spreads out on impact and ussually doesn't exit the target) shot into a mans palm from ten feet away would impart a force on the rest of his body equal to being hit by a semi truck. I know this is ridiculous...
A tennis player swings her 1000 g racket with a speed of 10.00 . She hits a 60 g tennis ball that was approaching her at a speed of 20.0 . The ball rebounds at 40.0 .
How fast is her racket moving immediately after the impact? You can ignore the interaction of the racket with her hand for the...