A device used for mixing consists of three identical thin rods extending from a central axle, all in the same plane, and spaced apart from each other by 120°. Each rod is 10.9 cm long, and attached to the end of each rod is a ball with a cross-sectional area 4.40 cm2. Each ball has a drag coefficient of 0.580. A motor drives the central axle, causing the device to rotate. (a) How much power (in W) must be supplied by the motor for the device to rotate at a constant speed of 1000 rev/min in air? (Use 1.20 kg/m3 for the density of air at 20°C.) (b) How much power (in W) must be supplied by the motor for the device to rotate at a constant speed of 1000 rev/min in water? (The density of water is 1.00 g/cm°, or 1,000 kg/m³.) W

A device used for mixing consists of three identical thin rods extending from a central axle, all in the same plane, and spaced apart from each other by 120°. Each rod is 10.9 cm long, and attached to the end of each rod is a ball with a cross-sectional area 4.40 cm2. Each ball has a drag coefficient of 0.580. A motor drives the central axle, causing the device to rotate. (a) How much power (in W) must be supplied by the motor for the device to rotate at a constant speed of 1000 rev/min in air? (Use 1.20 kg/m3 for the density of air at 20°C.) (b) How much power (in W) must be supplied by the motor for the device to rotate at a constant speed of 1000 rev/min in water? (The density of water is 1.00 g/cm°, or 1,000 kg/m³.) W

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter10: Rotational Motion

Section: Chapter Questions

Problem 64P: Review. A mixing beater consists of three thin rods, each 10.0 cm long. The rods diverge from a...

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