The Variation in the Pressure of Helium Gas, Measured from Its

question 45

Multiple Choice

The variation in the pressure of helium gas, measured from its equilibrium value, is given by ΔP = 2.9 × 10−⁵ cos (6.20x − 3 000t) where x and t have units m and s. Determine the speed (in m/s) of the wave.

• A) 1 515
• B) 153
• C) 484
• D) 828
• E) 101

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Definitions:

Periodic Inventory System

A system where inventory levels and cost of goods sold are determined at the end of the accounting period, rather than continuously.

Double Entry Accounting

An accounting system that maintains the balance of the accounting equation (Assets = Liabilities + Equity) by recording each transaction twice, once as a debit and once as a credit.

Single Entry Accounting

A method of bookkeeping that records only one side of each financial transaction, typically sufficient for smaller, simpler businesses.

Gross Profit

The difference between sales revenue and the cost of goods sold before accounting for other expenses.