The sciences concerned with the study of inanimate natural objects, including physics, chemistry, astronomy, and related subjects.
Answer:
(d) A strong electron-phonon interaction
Explanation:
Superconductivity -
The phenomenon of superconductivity is due to the attractive force between electrons from the exchange of the phonons that cause the bound pair of electrons known as cooper pairs .
A strong electron -phonon intercation is suitable condition for superconductivity and high resistance .
W=20 e(-kt)
A. Rearranging gives k= -(ln(w/20)/t
Substituting w= 10 and solving gives k=0.014
B. Using W=20e(-kt). After 0 hours, W=20. After 24 hours, W=14.29g. After 1 week (24x7=168h) W=1.9g
C. Rearranging gives t=-(ln(10/20)/k. Substituting w=1 and solving gives t=214 hours.
D. Differentiating gives dW/ dt = -20ke(-kt). Solving for t=100 gives dW/dt = 0.07g/h. Solving for t=1000 gives 0.0000002g/h
E. dW/dt = -20ke(-kt). But W=20e(-kt) so dW/dt = -kW
Power is defined as
P = I*V
where I is the current and V is the voltage
Ohm's law gives us the relation betwen Voltage and current in a resistive component
V = I*R , Then
P = V² / R
We solve for R,
R = (110 V)²/ 75W = 161.33 ohms
Potassium is the 19th element so it is B
