A Small Disk of Radius R₁ Is Fastened Coaxially to a Larger

question 65

Multiple Choice

A small disk of radius R₁ is fastened coaxially to a larger disk of radius R₂. The combination is free to rotate on a fixed axle, which is perpendicular to a horizontal frictionless table top, as shown in the overhead view below. The rotational inertia of the combination is I. A string is wrapped around the larger disk and attached to a block of mass m, on the table. Another string is wrapped around the smaller disk and is pulled with a force as shown. The tension in the string pulling the block is:

• A) R₁F/R₂
• B) mR₁R₂F/(I - mR₂²)
• C) mR₁R₂F/(I + mR₂²)
• D) mR₁R₂F/(I - mR₁R₂)
• E) mR₁R₂F/(I + mR₁R₂)

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Definitions:

Variable Costs

Expenses that vary directly with the volume of production or the degree of activity within a company.

Fixed Costs

Costs that do not vary with the volume of production or level of activity within a certain range. These are expenses that must be paid regardless of business activity, such as rent or salaries.

Required Return

The minimum expected yield by investors as compensation for the level of risk associated with an investment.

Initial Investment

The amount of money used to start a project, business, or investment.