22) (equation) bake cake until the center is 180deg F; cool to 120degF
A-given room temp of 70deg what is an exponential model for this data.
B- how long does it take for the cake to cool to desired temp
28) find amount in a continuously compounded amount for the given conditions.
principal:$2000
annual interest rate: 5.1%
time: 3 years
22)....I'm not a Physics major (or even minor!! ) but this one is based on Newton's Law of Cooling.......I don't believe we can answer the question unless we know how long it took for the center to cool from 180F to some lesser temperature.....we have to know this in order to find the constant of proportionality.....(Alan can correct me, if I'm wrong!!) ..also...is 120F the desired temperature??
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28) This is given by A = Pe(rt) where A is the accumulated amount, P is the amount invested, r is the interest rate (as a decimal) and t is the time....so we have....
A = 2000e(.051*3) = about $2330.65
22)....I'm not a Physics major (or even minor!! ) but this one is based on Newton's Law of Cooling.......I don't believe we can answer the question unless we know how long it took for the center to cool from 180F to some lesser temperature.....we have to know this in order to find the constant of proportionality.....(Alan can correct me, if I'm wrong!!) ..also...is 120F the desired temperature??
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28) This is given by A = Pe(rt) where A is the accumulated amount, P is the amount invested, r is the interest rate (as a decimal) and t is the time....so we have....
A = 2000e(.051*3) = about $2330.65
T(t) = TA + (TH - TA)e-kt
where,
T(t) = Temperature at time t,
TA = Ambient temperature (temp of surrounding)
TH = Initial temperature of the cake
k = constant of proportionality (negative because of cooling)
t = time.
Now, for A, we have,
120 = 70 + (180 - 70)e-kt, or $$\frac{}{}$$e-kt = 5/11
For B, i.e. to find t, you need k.