Fluid Mechanics
8th Edition
ISBN: 9780073398273
Author: Frank M. White
Publisher: McGraw-Hill Education
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Chapter 1, Problem 1.2CP
When a person ice skates, the surface of the ice actually melts beneath the blades, so that he or she skates on a thin sheet of water between the blade and the ice.
(a) Find an expression for total friction force on the bottom of the blade as a function of skater velocity V, blade length L, water thickness (between the blade and the ice) h, water viscosity
(b) Suppose an ice skater of total mass m is skating along at a constant speed of V0when she suddenly stands stiff with her skates pointed directly forward, allowing herself to coast to a stop. Neglecting friction due to air resistance, how far will she travel before she comes to a stop? (Remember, she is coasting on two skate blades.) Give your answer for the total distance traveled, x, as a function of V0, m, L, h,
(c) Find x for the case where V0= 4.0 m/s, m = 100 kg, L = 30 cm, W = 5.0 mm, and h = 0.10 mm. Do you think our assumption of negligible air resistance is a good one?
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Chapter 1 Solutions
Fluid Mechanics
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