Answer:
a) 2,945 mC
b) P(t) = -720*e^(-4t) uW
c) -180 uJ
Explanation:
Given:
i (t) = 6*e^(-2*t)
v (t) = 10*di / dt
Find:
( a) Find the charge delivered to the device between t=0 and t=2 s.
( b) Calculate the power absorbed.
( c) Determine the energy absorbed in 3 s.
Solution:
- The amount of charge Q delivered can be determined by:
dQ = i(t) . dt
- Integrate and evaluate the on the interval:
- The power can be calculated by using v(t) and i(t) as follows:
v(t) = 10* di / dt = 10*d(6*e^(-2*t)) /dt
v(t) = 10*(-12*e^(-2*t)) = -120*e^-2*t mV
P(t) = v(t)*i(t) = (-120*e^-2*t) * 6*e^(-2*t)
P(t) = -720*e^(-4t) uW
- The amount of energy W absorbed can be evaluated using P(t) as follows:
- Integrate and evaluate the on the interval:
A is the answer for the sentence
It is a metal because is saying that is a manually device
Answer:
well I took a look at them on the internet an also took a good look at the picture and Im pretty sure in the early 1900-1910
Explanation:
hope it helps:)
Answer:
a) the actual thermal efficiency is 15.17%
b) the maximum thermal efficiency is 29.55%
Explanation:
a) the actual thermal efficiency is for a heat engine is,
E actual = Power obtained / Necessary heat rate as input = P/q
q = F * c * (Tinitial - Tfinal) , F = mass flow rate , c=specific heat of water ( we assume c= 1 cal/gr°C = 4.186 J/gr°C= 4.186 kJ/kg°C)
q = 210 Kg/s * 4.186 kJ/kg°C (150°C - 90 °C) = 52743.6 kW
therefore
E actual = 8000 kW /52743.6 kW = 0.1517 = 15.17%
b) the maximum thermal efficiency for the same heat source and heat sink corresponds to the one of a Carnot engine. Where,
E max = 1 - Tc/Th , Th is the absolute temperature of the hot heat source and Tc is the absolute temperature of the cold heat sink.
therefore
Th= 150°C + 273 °C = 423 K
Tc= 25°C + 273°C = 298 K
thus
E max = 1- 298/423 = 0.2955 = 29.55%
