Answer:
Power is 15.41 hp
Work is 39205.18 Btu
Explanation:
The power to overcome the drag force is given by the formula:
P = (1/2)ρ v³ A Cd
where,
P = Power
ρ = Density of air = 0.075 lbm/ft³
v = speed of truck = (65 miles/hr)(1 hr/3600 s)(5280 ft/1 mile) = 95.33 ft/s
A = Area = 30 ft²
Cd = drag coefficient = 0.28
therefore,
P = (1/2)(0.075 lbm/ft³)(95.33 ft/s)³(30 ft²)(0.28)
P = (272926 ft².lbm/s³)(1 lbf/32.2 lbm.ft/s²)
P = (8476 ft. lbf/s)(1 hp/550 ft.lb/s)
<u>P = 15.41 hp</u>
Now, for the work of 1 hour:
Work = W = P x time
W = (15.41 hp)(2544 Btu/h / 1 hp)(1 h)
<u>W = 39205.18 Btu</u>
Answer:
Explanation:
= Density of water = 
= Change in volume = 
= Time elapsed = 1 minute = 60 seconds
Mass flow rate is given by
The mass flow rate is .
I believe the answer is true.
I hope this helps :)
Answer:
Explanation:
Let the force required be F . It is applied at the top of the box . The box is likely to turn about a corner . Torque of this force about this corner
= F x 2
This torque will try to turn the box . On the other hand the weight which is acting at CM will create a torque about the same corner . This torque will try to prevent the box to turn around the corner.
This torque of weight
= 100 x 1
= 100 pound ft.
For equilibrium
Torque of F = torque of weight.
F x 2 = 100
F = 50 pounds .
Answer:
C) 16.3 ml
Explanation:
Density is equal to the ratio between the mass of an object and its volume:
where
m is the mass
V is the volume
In our problem, we know:
- density of aluminium: 
- mass of the aluminium foil: 
So we can re-arrange the equation above and use these data to find the volume of the piece of aluminium foil:
