Newton's Law of Cooling
Tf=Ts+(Ti-Ts)e^(-kt) where Tf is temp at time t, Ts is temp of surroundings, Ti is temp of object/fluid. So we need to find k first.
200=68+(210-68)e^(-10k)
132=142e^(-10k)
132/142=e^(-10k)
ln(132/142)=-10k
k=-ln(132/142)/10
k≈0.0073 so
T(t)=68+142e^(-0.0073t) so how long until it reaches 180°?
180=68+142e^(-0.0073t)
112=142e^(-0.0073t)
112/142=e^(-0.0073t)
ln(112/142)=-0.0073t
t= -ln(112/142)/(0.0073)
t≈32.51 minutes
Answer:
Question 1 6 1/2
Step-by-step explanation:
Question 2 289/50
the answer for this is 84915
Answer:
1,041.9feet
Step-by-step explanation:
Given the height of the rocket expressed as
y = -16x² + 245x + 104
At maximum height, dy/dx = 0
dy/dx = -32x+245
0 = -32x+245
32x = 245
x = 245/32
x = 7.65625
Get the maximum height
Recall that;
y = -16x² + 245x + 104
Substitute the value of x;
y = -16(7.65625)² + 245(7.65625) + 104
y = -937.890625 + 1,875.78125 + 104
y = 1,041.890625feet
Hcne the maximum height to the nearest foot is 1,041.9feet