Resistance = Voltage/Current
Wattage = Voltage * Current
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That means the current drawn by the lamp is equal to 100 watts divided by 210 volts.
Resistance =
Explanation:
The given data is as follows.
mass = 227.8 kg, volume = 0.1189
It is known that formula for volume of a sphere is and density is as follows.
Density = ........ (1)
=
= 1915.895
Hence, putting the given values into equation (1) as follows.
Density =
1915.895 =
= 227.8
r = 0.305
Thus, we can conclude that radius of the sphere is 0.305 .
fluid friction<span> occurs when an object moves through a liquid or gas. the force needed to overcome </span>fluid friction <span>is usually less then that needed to overcome </span>sliding friction<span>. the </span>fluid<span> keeps the surface from making direct contact and thus </span>reducing friction<span>.</span>
Answer:
Explanation:
Given that,
Efficiency of Carnot engine is 47%
η =47%=0.47
The wasted heat is at temp 60°F
TL=60°F
Rate of heat wasted is 800Btu/min
Therefore, rate of heat loss QL is
QL' = 800×60 =48000
The power output is determined from rate of heat obtained from the source and rate of wasted heat.
Therefore,
W' = QH' - QL'
Note QH' = QL' / (1-η)
W' = QL' / (1-η) - QL'
W'=QL' η / (1-η)
W'= 48000×0.47/(1-0.47)
W'=42566.0377 BTU
1 btu per hour (btu/h) = 0.00039 horsepower (hp)
Then, 42566.0377×0.00039
W'=16.6hp
Which is approximately 17hp
b. Temperature at source
Using ratio of wanted heat to temp
Then,
TH / TL = QH' / QL'
TH = TL ( QH' / QL')
Since, QH' = QL' / (1-η)
Then, TH= TL( QL' /QL' (1-η))
TH=TL/(1-η)
TL=60°F, let convert to rankine
°R=°F+459.67
TL=60+459.67
TL=519.67R
TH=519.67/(1-0.47)
TH=980.51R
Which is approximately 1000R
Work+Force*Distance. Rearranging, F=W/d. Calculating, the force must be 0.0215 N.