Alpha Geek

(8)

$10/per page/Negotiable

About Alpha Geek

Levels Tought:
University

Expertise:
Accounting,Algebra See all
Accounting,Algebra,Architecture and Design,Art & Design,Biology,Business & Finance,Calculus,Chemistry,Communications,Computer Science,Environmental science,Essay writing,Programming,Social Science,Statistics Hide all
Teaching Since: Apr 2017
Last Sign in: 345 Weeks Ago, 4 Days Ago
Questions Answered: 9562
Tutorials Posted: 9559

Education

  • bachelor in business administration
    Polytechnic State University Sanluis
    Jan-2006 - Nov-2010

  • CPA
    Polytechnic State University
    Jan-2012 - Nov-2016

Experience

  • Professor
    Harvard Square Academy (HS2)
    Mar-2012 - Present

Category > Engineering Posted 08 May 2017 My Price 7.00

Determine how long it will be before the log ignites

A long cylindrical wood log (k = 0.17 W/m · °C and α = 1.28 x 107 m2/s) is 10 cm in diameter and is initially at a uniform temperature of 15°C. It is exposed to hot gases at 550°C in a fireplace with a heat transfer coefficient of 13.6 W/m2· °C on the surface. If the ignition temperature of the wood is 420°C, determine how long it will be before the log ignites.

Answers

Alpha Geek
(8)
Status NEW Posted 08 May 2017 08:05 AM My Price 7.00

-----------

Attachments

file 1494232161-Answer.docx preview (73 words )
A----------- lo-----------ng -----------cyl-----------ind-----------ric-----------al -----------woo-----------d l-----------og -----------(k -----------= 0-----------.17----------- W/-----------m Â-----------· Â-----------°C -----------and----------- α----------- = -----------1.2-----------8 x----------- 10-----------7 -----------m2/-----------s) -----------is -----------10 -----------cm -----------in -----------dia-----------met-----------er -----------and----------- is----------- in-----------iti-----------all-----------y a-----------t a----------- un-----------ifo-----------rm -----------tem-----------per-----------atu-----------re -----------of -----------15Â-----------°C.----------- It----------- is----------- ex-----------pos-----------ed -----------to -----------hot----------- ga-----------ses----------- at----------- 55-----------0°-----------C i-----------n a----------- fi-----------rep-----------lac-----------e w-----------ith----------- a -----------hea-----------t t-----------ran-----------sfe-----------r c-----------oef-----------fic-----------ien-----------t o-----------f 1-----------3.6----------- W/-----------m2Â-----------· Â-----------°C -----------on -----------the----------- su-----------rfa-----------ce.----------- If----------- th-----------e i-----------gni-----------tio-----------n t-----------emp-----------era-----------tur-----------e o-----------f t-----------he -----------woo-----------d i-----------s 4-----------20Â-----------°C,----------- de-----------ter-----------min-----------e h-----------ow -----------lon-----------g i-----------t w-----------ill----------- be----------- be-----------for-----------e t-----------he -----------log----------- ig-----------nit-----------es.----------- ----------- -----------
Not Rated(0)