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:
a magnet that retains its magnetic properties in the absence of an inducing field or current
Answer:
The impedance of the inductor is ω L:
This is in parallel wth R giving a resistance of the parallel combination:
1 / Rp = 1 / ω L + 1 / R
Rp = (ω L * R) / (ω L + R) for the impedance of the parallel combination
Total resistance (impedance) Rt = Rp + R2 = Z
One can use the term impedance to show that the resulting current is not in phase with the resulting voltage
phase angle φ - cos φ = ω L / Rt
V = I Z shows the relation of voltage and urrent
Electricity is a compound