You place a drop of blue food coloring in a cup of cold water and another drop of food coloring in a cup of hot water. Which observation is correct and why? A The food coloring in the hot water will spread more slowly than in the cold water because water molecules move more slowly when hot. B The food coloring in the hot water will spread more quickly than in the cold water because water molecules move more quickly when hot. C The food coloring in the cold water will spread more quickly than in the hot water because water molecules move more quickly when cold. D The food coloring in the cold water will spread at the same rate at the food coloring in the hot water because water molecules at any temperature move at the same rate.

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?

What is the speed of an object at a given moment?

An ideal otto cycle has a compression ratio of 10.5, takes in air at 90 kpa and 40°c, and is repeated 2500 times per minute. using constant specific heats at room temperature, determine the thermal efficiency of this cycle and the rate of heat input if the cycle is to produce 90 kw of power.