the average energy usage of a refrigerator is C(t)=1486e^-0.073t + 500
t is measured in years with t=0 corrisponding to 1972.
So here is the question...
All refrigerators made as of Jan 1 1990 must meet 950k-Wh/year max energy consumtion standard. Show that this refrigerator meets that standard.
So I thing that the answer is
C(18) =1486e^-0.073(18) + 500
Am I right or am I crazy?
2007-05-30 05:21:19 · 3 answers · asked by clawedstar 1 in Science & Mathematics ➔ Mathematics
You are right.
You are given that year t=0 is 1972.
Then 1990 would be (1990-1972) = 18.
For 1990,
C(18) = 1486e^-0.073t + 500
C(18) = 1486 * e^(-0.073 * 18) + 500
C(18) = 1486 * 0.268743 + 500
C(18) = 399.352 + 500
C(18) = about 899
Since that's under 950, it meets the standard.
2007-05-30 05:24:54 · answer #1 · answered by McFate 7 · 0⤊ 0⤋
In 1972 this refrigerator used 1986 kwh/y.
In 1990 this refrigerator consumed 899 kwh/y.
In 2006 it consumed 624.19 kwh./y.
It must be a magic refrigerator that consumes less energy each year until it reaches minimum usage of 500 kwh/y.
Actually, it could be reduced to zero if you unplugged it.
Something goofy here.
2007-05-30 12:52:27 · answer #2 · answered by ironduke8159 7 · 0⤊ 0⤋
It is correct
2007-05-30 12:26:07 · answer #3 · answered by Rob 3 · 0⤊ 0⤋