A Pair of Railway Boxcars Are Moving Toward Each Other

question 21

Multiple Choice

A pair of railway boxcars are moving toward each other on a rail with negligible friction. One boxcar is twice the mass of the other. On collision, the boxcars couple to each other. In order for the coupled pair to have zero velocity (relative to a bystander next to the track) after the collision, what is the ratio of velocities of the more massive to the less massive boxcar before the collision?

• A)1/2
• B)1/3
• C)-1/3
• D)-1/2

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Definitions:

Expense Account

An account where business-related expenses are recorded, often used for tracking purposes for budgeting or tax deductions.

Incurred

Expenses, losses, or liabilities that have been suffered or assumed in the course of conducting business.

Matching Principle

An accounting concept that requires expenses to be recorded in the same period as the revenues that are generated as a result of those expenses.

Expenses

It refers to the outflow of cash or other valuable assets from a person or company to another entity as a result of purchasing goods or services.