We've seen that bees develop a positive charge as they fly through the air. when a bee lands on a flower, charge is transferred, and an opposite charge is induced in the earth below the flower. the flower and the ground together make a capacitor; a typical value is 0.60 pf. if a flower is charged to 30 v relative to the ground, a bee can reliably detect the added charge and then avoids the flower in favor of flowers that have not been recently visited approximately how much charge must a bee transfer to the flower to create a 30 v potential difference?

In a wind tunnel the speed changes as the cross sectional area of the tunnel changes. if the speed in a 6' x 6' square test section is 100 mph, what was the speed upstream of the test section where the tunnel measured 20' x 20'? use conservation of mass and assume incompressible flow. conservation of mass requires that as the flow moves through a path or a duct the product of the density, velocity and cross sectional area must remain constant; i.e., that ova-constant. a model is being tested in a wind tunnel at a speed of 100 mph if the flow in the test section is at sea level standard conditions, what is the pressure at the model's stagnation point? (a) the tunnel speed is being measured by a pitot-static tube connected to a u- tube manometer. what is the reading on that manometer in inches of water? (b) at one point on the model a pressure of 2058 psf is measured. what is the local airspeed at that point?

Which is not a characteristic of a heat pump? a. it is used in air conditioners. b. it uses a refrigerant. c. it requires no work. d. it reverses the normal flow of thermal energy.

Which of the following are guidelines to follow for obtaining accurate observations