An umbrella has a tendency to move upward when it is windy principally because
A)moving air over the curved surface produces reduced pressure against its top.
B)air moves up into the "bowl" and pushes upward with increased pressure.
C)buoyancy increases with increasing wind speed.
D)the umbrella is simply pushed upward by the wind.
This effect was first accurately described by
E)Galileo.
F)Newton.
G)Bernoulli.
H)Einstein.
I)Archimedes.

Question

Quizplus · Accepted Answer

A) The principle that explains why an umbrella tends to move upward in windy conditions is related to Bernoulli's principle. As air moves over the curved surface of the umbrella, it speeds up and its pressure decreases compared to the still air underneath. This pressure difference creates an upward lift. G) Bernoulli's principle, named after Daniel Bernoulli who first described this effect, explains how the pressure of a moving fluid (including air) decreases as its velocity increases.

An Umbrella Has a Tendency to Move Upward When It