Answer:

Explanation:
Newton's law of cooling
Rate of cooling

Where To is the surrounding temperature
T is object temperature at any time t
now by removing proportionality sign

Now by separating variables


So

Where C is constant

C' is also a constant and it can be find by using boundary conditions.
Answer: 3.9 MW
Explanation:
1 W = 1 J/s
260000 J/s (15 s) = 3,900,000 = 3.9 MW
Answer:
Hence the amount of heat transfer is 918.75 Btu.
Explanation:
Now,
Answer:
425 m
Explanation:
From the question,
v = 2x/t.................... Equation 1
Where v = speed of sound in air, x = Length of the lake, t = time.
make x the subject of the equation
x = vt/2............... Equation 2
Given: t = 2.5 s
Constant: v = 340 m/s.
Substitute these values into equation 2
x = 340(2.5)/2
x = 425 m.
Hence the length of the lake is 425 m
If Voq doubles, abN gets multiplied by 16 .
If Voq=3, abN=81 .