The Length $l$ , Width $w$ And Height $h$ Of a Box Change with Time

question 110

Short Answer

The length $l$ , width $w$ and height $h$ of a box change with time. At a certain instant the dimensions are $l = 3$ and $w = h = 4$ , and $l$ and $w$ are increasing at a rate of $10 \mathrm {~m} / \mathrm { s }$ while $h$ is decreasing at a rate of 1 $\mathrm { m } / \mathrm { s }$ . At that instant find the rates at which the surface area is changing.

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Definitions:

Developmental Level

The stage of growth or progression in physical, emotional, intellectual, or social development typical for a certain age or group.

Superego

In psychoanalytic theory, the part of the personality responsible for the internalization of societal and parental standards of conduct, operating on the morality principle.

Fixation

According to Freud, a condition in which the id, ego, and superego do not mature properly and are frozen at an early stage of development.

Libido

The sexual energy that fuels the id.