Problem: A hurricane wind blows across an 8.00m×16.0m flat roof at a speed of 140 km/h.Part A:Is the air pressure above the roof higher or lower than the pressure inside the house? Pick one. Explain.a. The pressure above the roof is lower due to the lower velocity of the air.b. The pressure above the roof is lower due to the higher velocity of the air.c. The pressure above the roof is higher due to the lower velocity of the air.d. The pressure above the roof is higher due to the higher velocity of the air.Part B: What is the pressure difference Δp=pinside−poutside? Use 1.28 kg/m3 for the density of air. Treat the air as an ideal fluid obeying Bernoulli's equation.Express your answer using two significant figures. Answer should be in (Pa)Part C: How much force is exerted on the roof?Express your answer to two significant figures and include the appropriate units. Be sure to give the units in the answer.Part D: If the roof cannot withstand this much force, will it "blow in" or "blow out"?If the roof cannot withstand this much force, will it "blow in" or "blow out"? Pick onea. The roof will blow inward (down), because the pressure inside the house is greater than the pressure on the top of the roof.b. The roof will blow outward (up), because pressure inside the house is greater than pressure on the top of the roof.c. The roof will blow outward (up), because pressure inside the house is less than pressure on the top of the roof.d. The roof will blow inward (down), because pressure inside the house is less than pressure on the top of the roof.

FREE Expert Solution

Part A.

We need Bernoulli's principle to determine where the pressure is more. 

According to Bernoulli's principle, the fluid pressure is lowered in the areas where the flow velocity is increased. 

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Problem Details

A hurricane wind blows across an 8.00m×16.0m flat roof at a speed of 140 km/h.

Part A:

Is the air pressure above the roof higher or lower than the pressure inside the house? Pick one. Explain.

a. The pressure above the roof is lower due to the lower velocity of the air.

b. The pressure above the roof is lower due to the higher velocity of the air.

c. The pressure above the roof is higher due to the lower velocity of the air.

d. The pressure above the roof is higher due to the higher velocity of the air.

Part B: What is the pressure difference Δp=pinside−poutside? Use 1.28 kg/m3 for the density of air. Treat the air as an ideal fluid obeying Bernoulli's equation.

Express your answer using two significant figures. Answer should be in (Pa)

Part C: How much force is exerted on the roof?

Express your answer to two significant figures and include the appropriate units. Be sure to give the units in the answer.

Part D: If the roof cannot withstand this much force, will it "blow in" or "blow out"?

If the roof cannot withstand this much force, will it "blow in" or "blow out"? Pick one

a. The roof will blow inward (down), because the pressure inside the house is greater than the pressure on the top of the roof.

b. The roof will blow outward (up), because pressure inside the house is greater than pressure on the top of the roof.

c. The roof will blow outward (up), because pressure inside the house is less than pressure on the top of the roof.

d. The roof will blow inward (down), because pressure inside the house is less than pressure on the top of the roof.

Frequently Asked Questions

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Bernoulli's Equation concept. If you need more Bernoulli's Equation practice, you can also practice Bernoulli's Equation practice problems.

What professor is this problem relevant for?

Based on our data, we think this problem is relevant for Professor Borzenets' class at TAMU.