The rate of cooling a metal ball can be expressed as dT -k(T – Ta) %3D dt Where T= temperature of the metal ball (C), Ta = temperature of water (C), t= time (min) and k= the proportionality constant (min-!). A metal ball at initial temperature of 90 C is dropped into water reservoir that is held at a constant value of Ta= 15 °C. Estimate how long it takes the ball to cool to less than 40 °C if k= 0.2 min-1.

The rate of cooling a metal ball can be expressed as dT -k(T – Ta) %3D dt Where T= temperature of the metal ball (C), Ta = temperature of water (C), t= time (min) and k= the proportionality constant (min-!). A metal ball at initial temperature of 90 C is dropped into water reservoir that is held at a constant value of Ta= 15 °C. Estimate how long it takes the ball to cool to less than 40 °C if k= 0.2 min-1.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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Numerical Method

Answer (in 2 decimal places) :_____min

The rate of cooling a metal ball can be expressed as
dT
-k(T – Ta)
dt
Where T= temperature of the metal ball (C), Ta= temperature of water (C), t = time (min) and
k= the proportionality constant (min-!). A metal ball at initial temperature of 90 °C is dropped into
water reservoir that is held at a constant value of Ta = 15 °C. Estimate how long it takes the ball
to cool to less than 40 °C if k = 0.2 min-1.

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