Answer:
μ=0.329, 2.671 turns.
Explanation:
(a) ln(T2/T1)=μβ β=angle of contact in radians
take T2 as greater tension value and T1 smaller, otherwise the friction would be opposite.
T2=5000 lb and T1=80 lb
we have two full turns which makes total angle of contact=4π radians
μ=ln(T2/T1)/β=(ln(5000/80))/4π
μ=0.329
(b) using the same relation as above we will now compute the angle of contact.
take greater tension as T2 and smaller as T1.
T2=20000 lb T1=80 lb μ=0.329
β=ln(20000/80)/0.329=16.7825 radians
divide the angle of contact by 2π to obtain number of turns.
16.7825/2π =2.671 turns
Its safe because it isn't something with electricity
Answer:
What's your question?
Explanation:
I'm not able to understand it....
Sorry.
Answer:
COP_max = 18.69
Explanation:
We are given;
Heated space temperature; T_H = 26°C = 273K + 26 = 299K
Temperature at which heat is extracted; T_L = 10°C = 273 + 10 = 283K
Now the Coefficient of performance (COP) of a heat pump will be a maximum when the heat pump operates in a reversible manner. The COP of a reversible heat pump depends on the temperature limits in the cycle only and is determined by the formula;
COP_max = 1/(1 - (T_L/T_H))
Thus,
COP_max = 1/(1 - (283/299))
COP_max = 1/(1 - 0.9465)
COP_max = 1/0.0535 = 18.69
