R(t) = 4t³ I + (2t + 3)j Is the Position

question 141

Multiple Choice

r(t) = 4t³ i + (2t + 3) j is the position vector of a particle moving in a plane. Find the speed at t = 1.

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Definitions:

Rectus Abdominus

A long muscle running from the pubis to the ribcage, involved in flexing the lumbar spine and stabilizing the pelvis and core.

Pectoralis Minor

A thin, triangular muscle located beneath the pectoralis major, involved in movements of the shoulder blade, including drawing it downward and forward.

Internal Intercostal

Muscles located between the ribs that contract during exhalation, aiding in the forced expiration of air from the lungs.

Coracobrachialis

A muscle in the shoulder that flexes and adducts the arm.