A Wind with Speed 45 M/s Blows Across a Roof $\times$

question 14

Multiple Choice

A wind with speed 45 m/s blows across a roof 20 m long and 12 m wide.The pressure inside the room is 1 atm.What is the net force on this roof due to the pressure difference inside and outside the roof? (The density of air is equal to 1.3 kg/m³.)

• A)3.2 \(\times\) 10⁵ N
• B)2.4 \(\times\) 10⁷ N
• C)6.3 \(\times\) 10⁵ N
• D)7.0 \(\times\) 10³ N
• E)3.2 \(\times\) 10⁸ N

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Definitions:

Autonomous Investment

Investment that is not influenced by the current level of income or production, often driven by technological innovations or changes in policy.

Aggregate Expenditure Line

A visual depiction in macroeconomics illustrating the overall expenditures on goods and services within an economy across different income levels.

Marginal Propensity

The tendency of a person to spend an additional unit of currency; often relates to income in the context of marginal propensity to consume or save.

Simple Multiplier

The ratio used to estimate the proportional amount of increase, or decrease, in final income that results from an injection, or withdrawal, of spending.