Waiting on the alfalfa tea and Newton’s law of cooling
[1]To make herbal tea, Layla pours boiling water into a teacup and onto a teabag.
Immediately after pouring, she lowers a thermometer into the teacup.
When the thermometer reaches its highest reading, Layla starts her timing.
The highest temperature achieved was T = 99°C at a time when t = 0 seconds.
After 42 seconds, the tea temperature has descended to 96.8°C.
If Layla left her tea out all day it would cool to a steady state temperature of 19°C.
Layla will not drink tea hotter than 82°C.
How long t from the time she started timing will she have to wait for cooling?
t = ______ seconds
First correct answer to arrive at [email protected] [2] wins a Tucker’s Ice Cream gift card.
Last week’s winner [3] was Matt Bliven with l = 225 centimeters.
Jeff Smith is a former Math teacher and a retired US Navy Lieutenant Commander. Reach him at [email protected] [2].