If R(t) Is the Position Vector of a Particle in the Plane

question 63

Multiple Choice

If r(t) is the position vector of a particle in the plane at time t, find the indicated vector.
-Find the acceleration vector. r(t) = (cos 4t) i + (5 sin t) j

• A) a = (-4 cos 4t)i + (5 sin t)j
• B) a = (-16 cos 4t)i + (-5 sin t)j
• C) a = (-16 cos 4t)i + (-25 sin t)j
• D) a = (16 cos 4t)i + (-5 sin t)j

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Definitions:

Medullary Osmotic Gradient

A concentration gradient of solutes in the kidney's medulla that helps in the reabsorption of water from urine, contributing to the body's water balance.

Loop Of Henle

A section of the nephron in the kidney that is responsible for concentrating urine and conserving water.

Glomerular Filtration Membrane

A selective filtration barrier in the kidneys that separates blood plasma from the filtrate, leading to urine formation.

Distal Convoluted Tubule

A portion of the kidney nephron that functions in the reabsorption of water, sodium, and chloride and in the secretion of potassium and hydrogen ions.