Calculate the Displacement Amplitude (In M)of a 20 KHz Sound $\rho$

question 23

Multiple Choice

Calculate the displacement amplitude (in m) of a 20 kHz sound wave in helium if it has a pressure amplitude of 8.0 *10 ^{- 3} N/m².( $\rho$ = 0.179 kg/m³,v = 972 m/s. )

• A)2.9 *10 ^{- 10}
• B)3.7 *10 ^{- 10}
• C)7.8 * 10 ^{- 9}
• D)2.4 *10 ^{- 9}
• E)1.9*10 ^{- 10}

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Definitions:

LIFO Periodic

A method of inventory valuation where the last items placed in inventory are the first ones to be recorded as sold, used in periodic inventory accounting systems.

Cost of Goods Sold

Expenses directly linked to the creation of goods sold by a business, such as materials and labor.

Inventory Units

The individual items or quantifiable segments of products that a business holds in its inventory, each possibly having a different value or cost basis.

Perpetual LIFO

Perpetual Last-In-First-Out is an inventory cost method assuming that the last items added to inventory are the first sold, continually updating inventory and cost of goods sold values.