In physics, a field refers to a quantity that has a value for every point in a space. In a sense, a field is like a function in mathematics; the input is some point in space and the output is some object. A familiar example of a field is elevation. At every point on earth's surface, we can ask how far above or below sea level we are. 1) (Introduction) For the following physical quantities, decide which are fields and which are not. You may remember that vectors are physical quantities that have a direction (and magnitude) and scalars physical quantities that are just numbers. If you decide the quantity is a field, s it a scalar field?
a) Temperature at ground level
b) Wind velocity at 100 feet above the ground.
c) Gravitational force on Roessler Hall.
d) Height of a person in your group.
e) Height (above sea level) of the ground.
f) Slope of the surface of the earth.

The inside surface of a cylindrical-shaped cave of inner diameter 1.0 m is continuously covered with a very thin layer of water. the cave is very long and it is open on both ends. the water on the cave surface is at a constant temperature of 15.5 °c. the cave is constantly exposed to wind such that 15.5 °c air flows through the cave at 4.5 m/s. the kinematic viscosity of the air is 14.66 x 10-6 m2/s and the molecular diffusion coefficient of water vapor in the air is 0.239 x 10-4 m2/s. because the cave diameter is so large, the flow of wind down the length of the cave, in the x direction, can be treated like it is external flow and the cave surface can be approximated as flat where appropriate. calculate the x value, in a) the transition to turbulent flow occurs at rex meters, where the air flow transitions from laminar to turbulent along the inside surface of the cave b) calculate the x value, in meters, where the bulk steady state concentration of water vapor in the air flowing in the cave is 10% of the saturation concentration. assume the air at the surface of the water layer is 100% saturated with water vapor. assume the wind entering the cave contained no moisture before it entered the cave. take into account the transition from laminar to turbulent flow when solving part b