Engineering - May 2007

ive been given a problem, and one part to the problem is i have to find the velocity ratio of 3 pulleys lifting a block of mass 500kg, using one rope. the effort, E, is given as E=(0.4W+0.5)kN, where W is the weight in kN of the block. how is this question possible?

2007-05-14 06:38:09 · 1 answers · asked by onetrickhorse 1

By back up power supply, I mean like one for a computer in case the power goes out. For example:

Power Supply: http://www.powercom-usa.com/ProductDetail.asp?ID=3618 \

Electric Lawnmower: http://www.homedepot.com/prel80/HDUS/EN_US/diy_main/pg_diy.jsp?CNTTYPE=PROD_META&CNTKEY=misc%2fsearchResults.jsp&BV_SessionID=@@@@0216561975.1179162371@@@@&BV_EngineID=ccdhaddkmegeielcgelceffdfgidgll.0&MID=9876

Or do you think it will destroy the electric lawnmower and/or power supply?

2007-05-14 06:14:51 · 4 answers · asked by gomakemeasandwich 4

electricity question

2007-05-14 05:47:10 · 7 answers · asked by Albert J 1

Crude pipelines have specs on a number of properties, including viscosity and density. Specifying viscosity makes sense, but why density (or API gravity)? That is, what consequences (I assume negative) does the pipeline suffer if the API gravity is below 19° (or the density above 0.94 g/cm3), which is the spec I most often hear?

2007-05-14 05:01:48 · 2 answers · asked by Braveheart 1

Can steel buildings really collapse from fire damage?

2007-05-14 04:12:02 · 4 answers · asked by Matthew A 1

can laser beams transmit the same amount of data as fiber optic cables?

2007-05-14 04:00:30 · 4 answers · asked by Anonymous

what are the free web sites which provides such help

2007-05-14 03:52:38 · 3 answers · asked by Mohammed R 1

2007-05-14 03:40:36 · 11 answers · asked by Anonymous

how does it work, diagrams, examples, anything

2007-05-14 03:21:54 · 10 answers · asked by Anonymous

I want to learn about how to design a board with a microprocessor to be able to program and use as a microcontroller.

2007-05-14 03:19:21 · 4 answers · asked by Aref K 1

I'm about to mount three 12" subwoofers into my car. They will be mounted in a triangular pattern, leaving two of the subwoofers about one foot away from the hard drives of a computer system I've installed in my car. How can I dampen the magnetic field to protect the disk drives, or would it even be necessary?

2007-05-14 03:13:57 · 5 answers · asked by Ryan Detwiler 2

I am interested in knowing what are the most interesting and useful engineering courses. I have taken all the basic science and math classes (through Calculus) and now want to know what I might enjoy in engineering.

2007-05-14 02:51:23 · 10 answers · asked by MillMatt 1

Dear All,
I would like to ask, why are companies still using analog filters. All the filtering can easily be done by digital filtering. Why is the need of analog filters still necessary. All the filtering can be done by digital filters.
I want to eliminate 50Hz noise from EEG. Cant I just record the signal and eliminate 50Hz noise. Is a filter implemented in hardware better?
why should I use analog filters when I can use digital filters. And any way I have more options when using digital filtering and I do not loose the neighboring frequencies, in a band stop filter when I use digital filters.
thank you.
Munir Afzal Bhatti

2007-05-14 01:47:58 · 4 answers · asked by mbhatti2000 2

And please dont say use it less.
Ive heard magnets work?
Im rebelling against british gas.

2007-05-14 01:09:05 · 9 answers · asked by Chimplad 2

i lucky got into structural engineering field of UC San Diego.
i worry about if this major focus enough on the subjects of civil engineering, would the company i interview with in the future think that i didnt graduated from an university that has concrete civil engineering course ?

2007-05-13 18:49:57 · 3 answers · asked by Rogerwonder 1

Does a a voltmeter connect in series or parralel with a circuit?

2007-05-13 17:44:14 · 9 answers · asked by Anonymous

2007-05-13 16:44:09 · 1 answers · asked by jhoanamarie_1216 1

2007-05-13 16:41:54 · 1 answers · asked by jhoanamarie_1216 1

It is generally accepted that a heavy truck can't stop in the same distance that a car can stop. But from the perspective of basic physics, I don't see why this should be true.

If the truck's mass is 30 times that of a car, then its tires are pressed against the road surface with 30 times as much force.
And that force times the coefficient of friction gives the maximum amount of stopping force that can be applied, which is also 30 times as great as the maximum stopping force of the car.
And by applying 30 times as much stopping force to a mass 30 times as great, the truck's maximum deceleration should be exactly equal to the car's deceleration.
So why do trucks (supposedly) need more space to stop?
Is it that they can't achieve this theoretical maximum rate of deceleration? (They do, after all, have more moving parts?)
Or is it that they are harder to control at maximum deceleration, so drivers are reluctant to do a maximum stop?
Or is it just an old wives' tale to make us cautious?

2007-05-13 16:35:23 · 12 answers · asked by actuator 5

The length of Jim's leader is always 2 ft. shorter than the length of his fishing rod. If the product of the length of the leader and the length of the rod equals strength of his line in lbs. and he uses 16 lb line, what is the length of his leader?

2007-05-13 15:16:24 · 2 answers · asked by tlcnc 2

How much a mole of austenite in stainless steel weigh in gram? what is its density? (approximates are fine)

2007-05-13 13:24:07 · 2 answers · asked by barzan07 1

What supplies do i need...how do i build it...

2007-05-13 13:05:36 · 1 answers · asked by kornfrk2727 2

2007-05-13 12:25:13 · 4 answers · asked by findsouls f 1

2007-05-13 06:30:46 · 1 answers · asked by irfan b 1

2007-05-13 04:58:17 · 5 answers · asked by pandamay 1

is it possible to cut off the amperage without affecting the voltage? i want to get a 9V 300mA...

2007-05-13 03:51:58 · 6 answers · asked by Anonymous

2007-05-13 03:46:18 · 9 answers · asked by aetheka 1

The output voltage should give 0-5 V with the maximum current of 500mA. should use 1 Op-Amp and 1 MOSFET (no commercial regulator chip).
the Voltage is varied using a potentiometer

I tried to do using circuit maker but the voltage step if too big when the potentiometer is varied

2007-05-13 03:21:15 · 4 answers · asked by Anonymous

I'm searching for information and books on simple machines such as levers, pulleys, inclines, wedges, etc. and was wondering if someone could enlighten me as to what science this is studied in?..Mechanics?..Mechanical Engineering?..Physics?
I'm stumped at the moment as it seems that all the above mentioned categories involves these simple machines, but I'd like to find a narrower category that these fit in so I can search for books on the subject. I'm especially interested in moving very heavy objects by hand with the use of pulleys, inclines and levers, and I'm being overwhelmed with search results online. Any suggestions?
Thanks

2007-05-13 02:54:48 · 7 answers · asked by hk538 1

what tonage of AC unit would it take to cool a room 23'10x16'6

2007-05-13 01:43:36 · 2 answers · asked by Michael A 1