Answer:
ρ=0.0102lbm/ft^3
Explanation:
To solve this problem we must take into account the equation of continuity, this indicates that the sum of the mass flows that enter a system is equal to the sum of all those that leave.
Therefore, to find the mass flow of exhaust gases we must add the mass flows of air and fuel.
m=0.59+60=60.59lbm/s( mass flow of exhaust gases)
The equation that defines the mass flow (amount of mass that passes through a pipe per unit of time) is as follows
m=ρVA
Where
ρ=density
V=velocity
m=mass flow
A=cross-sectional area
solving for density
ρ=m/VA
ρ=60.59/{(1485)(4)}
ρ=0.0102lbm/ft^3
Answer:
20,000,000 N
Explanation:
First find the acceleration:
a = Δv / Δt
a = (0 − 40 m/s) / 0.010 s
a = -4000 m/s²
Next use Newton's second law to find the force on the car:
F = ma
F = (5000 kg) (-4000 m/s²)
F = -20,000,000 N
According to Newton's third law, the force on the wall is equal and opposite the force on the car.
F = 20,000,000 N
Answer: A. If the surface aquifer has a high water table
Explanation:
The water table refers to the water level underground. If it is high, it means that the water underground is close to the surface such that if a well was dug, it would not need to be dug too far for water to be seen.
When heavy rain falls, flooding is avoided if the water is either able to run off efficiently or if the ground is able to absorb the water. When the water table is high, it means that the ground will not be able to absorb much because the water is already close to the surface which means that should heavy rain fall, there will most likely be a flood.
