In this lab we will drop a steel ball (Psteel = 8000 kg/m³, rball = 2.18 x103 m) through the air (Nair = 1.8 x10 Pa.s, Pair = 1.29 kg/m³), and through a viscous soap solution (nsoap = 9.0 Pa.s [you will measure this number in the lab, but use this number for the prelab], Psoap = 1000 kg/m³). %3D 1 Pa = 1 N/m?. Calculate the terminal speed of the ball falling through the air, assuming that inertial drag is the dominant contributor. (For a sphere CD = and A is the area of the circle of radius r of the ball). Neglecting drag, estimate the time in seconds it takes for the steel ball to reach the terminal speed found in part 2 (1). Neglecting drag, estimate how far the ball would have travelled before reaching its terminal speed and comment on whether it is reasonable to neglect drag when studying the motion of this ball as it falls through the air from rest from the top of a 30 cm tall beaker or even from the ceiling of the room. O Neglecting drag it would take 36 m to reach the terminal velocity. Since a room is about 1/12 of this distance it is a good approximation to neglect drag even when dropping the steel ball from the ceiling of the room through the air.

In this lab we will drop a steel ball (Psteel = 8000 kg/m³, rball = 2.18 x103 m) through the air (Nair = 1.8 x10 Pa.s, Pair = 1.29 kg/m³), and through a viscous soap solution (nsoap = 9.0 Pa.s [you will measure this number in the lab, but use this number for the prelab], Psoap = 1000 kg/m³). %3D 1 Pa = 1 N/m?. Calculate the terminal speed of the ball falling through the air, assuming that inertial drag is the dominant contributor. (For a sphere CD = and A is the area of the circle of radius r of the ball). Neglecting drag, estimate the time in seconds it takes for the steel ball to reach the terminal speed found in part 2 (1). Neglecting drag, estimate how far the ball would have travelled before reaching its terminal speed and comment on whether it is reasonable to neglect drag when studying the motion of this ball as it falls through the air from rest from the top of a 30 cm tall beaker or even from the ceiling of the room. O Neglecting drag it would take 36 m to reach the terminal velocity. Since a room is about 1/12 of this distance it is a good approximation to neglect drag even when dropping the steel ball from the ceiling of the room through the air.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.9P: When a sphere falls freely through a homogeneous fluid, it reaches a terminal velocity at which the...

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