Answer:
No, the claim is not reasonable for 20 W electric power consumption.
It is reasonable for 40 W electric power consumption.
Explanation:
Power = (1/2)*mass flow rate*(square of velocity)
mass flow rate = 1 kg/s
velocity = 8 m/s
square of velocity = 64 m^2 / s^2
Power = (1/2)*(1)*(64)
Power = 32 W
For a fan that consumes 20 W power it is not possible to deliver more power than 20 W but this one is delivering 32 W hence it is a false claim.
For a fan that consumes 40 W it is indeed possible to deliver 32 W considering the efficiency. Hence this claim is reasonable.
Answer:
7.8 Mph
Explanation:
Rate of cycling = 1.1 rev/s
Rear wheel diameter = 26 inches
Diameter of sprocket on pedal = 6 inches
Diameter of sprocket on rear wheel = 4 inches
Circumference of rear wheel = \pi d=26\piπd=26π
Speed would be
\begin{gathered}\text{Rate of cycling}\times \frac{\text{Diameter of sprocket on pedal}}{\text{Diameter of sprocket on rear wheel}}\times{\text{Circumference of rear wheel}}\\ =1.1\times \frac{6}{4}\times 26\pi\\ =134.77432\ inches/s\end{gathered}Rate of cycling×Diameter of sprocket on rear wheelDiameter of sprocket on pedal×Circumference of rear wheel=1.1×46×26π=134.77432 inches/s
Converting to mph
1\ inch/s=\frac{1}{63360}\times 3600\ mph1 inch/s=633601×3600 mph
134.77432\ inches/s=134.77432\times \frac{1}{63360}\times 3600\ mph=7.65763\ mph134.77432 inches/s=134.77432×633601×3600 mph=7.65763 mph
The Speed of the bicycle is 7.8 mph
Answer:
a) 
(Ω-m)^{-1}
b) Resistance = 121.4 Ω
Explanation:
given data:
diameter is 7.0 mm
length 57 mm
current I = 0.25 A
voltage v = 24 v
distance between the probes is 45 mm
electrical conductivity is given as
![\sigma = \frac{0.25 \times 45\times 10^{-3}}{24 \pi [\frac{7 \times 10^{-3}}{2}]^2}](https://tex.z-dn.net/?f=%5Csigma%20%20%3D%20%5Cfrac%7B0.25%20%5Ctimes%2045%5Ctimes%2010%5E%7B-3%7D%7D%7B24%20%5Cpi%20%5B%5Cfrac%7B7%20%5Ctimes%2010%5E%7B-3%7D%7D%7B2%7D%5D%5E2%7D)
(Ω-m)^{-1}[/tex]
b)
![= \frac{57 \times 10^{-3}}{12.2 \times \pi [\frac{7 \times 10^{-3}}{2}]^2}](https://tex.z-dn.net/?f=%3D%20%5Cfrac%7B57%20%20%5Ctimes%2010%5E%7B-3%7D%7D%7B12.2%20%5Ctimes%20%5Cpi%20%5B%5Cfrac%7B7%20%5Ctimes%2010%5E%7B-3%7D%7D%7B2%7D%5D%5E2%7D)
Resistance = 121.4 Ω
1 liter = .264 gallon
1 km = .621 mile
this means that 58.3km/L is equal to 137.13mpg
so
500/137.13 = 3.65 gallons of gas
3.65 x 3.5 = $12.78
