What Force Is Required So That a Particle of Mass $m$

question 121

Multiple Choice

What force is required so that a particle of mass $m$ has the following position function?.
$$r ( t ) = 5 t ^ { 3 } \mathbf { i } + 10 t ^ { 2 } \mathbf { j } + 7 t ^ { 3 } \mathbf { k }$$

• A) \(\mathrm { F } ( t ) = 30 m t \mathbf { i } + 20 m \mathbf { j } + 42 m t \mathbf { k }\)
• B) \(\mathrm { F } ( t ) = 30 m t ^ { 2 } \mathbf { i } + 20 m \mathbf { j } + 42 m t \mathbf { k }\)
• C) \(\mathrm { F } ( t ) = 42 m t \mathbf { i } + 42 m \mathbf { j } + 20 m t \mathbf { k }\)
• D) \(\mathrm { F } ( t ) = m t ^ { 2 } \mathbf { i } + 5 m t \mathbf { j } + 10 m t ^ { 2 } \mathbf { k }\)
• E) \(\mathrm { F } ( t ) = 30 m t \mathbf { i } + 20 m \mathbf { j } + t \mathbf { k }\)

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Definitions:

Average Variable Cost

The average cost of variable inputs (like labor and materials) per unit of output produced.

Minimum

The lowest point on a nonlinear curve, where the slope changes from negative to positive.

Economic Profit

The difference between the total revenue received by a business and the total implicit and explicit costs of a business.

ATC

Average Total Cost, which is the sum of all production costs divided by the quantity of output produced.