Principles and Processes of Hydrology 1

Question 1

What is the water balance equation?

Answer 1

(P-E) + Uk + Ui + Q + deltaS = 0

Question 2

What are the 4 fundamental laws that form the basis of hydrology?

Answer 2

1. Conservation of mass
2. Newtons law of motion
3. laws of thermodynamics
4. Fick’s law of diffusion

Question 3

Dimension

Answer 3

The ratio of the magnitude of the quantity (of water) to the magnitude of a standard unit of measurement.

Question 4

Dimension of Force

Answer 4

[F] in Newton

Question 5

Dimension of Mass

Answer 5

[M] in kilograms

Question 6

Dimension of Length

Answer 6

[L] in meters

Question 7

Dimension of Time

Answer 7

[T] in seconds

Question 8

Dimension of Temperature

Answer 8

[Theta] in Kelvin

Question 9

Integers

Answer 9

[Mâ] where a is the integer

Question 10

How are units of Mass and units of Force related by Newtons 2nd law?

Answer 10

[F] = [M A] = [M L T^-2]

Question 11

Dimension of Energy (what it equals)

Answer 11

[E] = [F L]

Question 12

Dimensionless quantities

Answer 12

Quantities obtained by counting, denoted as [1]

Question 13

Units

Answer 13

The arbitrary standards in which magnitudes of quantities are expressed.
(Expresses the ratio of the magnitude of a quantity to the magnitude of an arbitrary standard)

Question 14

Systeme International (SI)

Answer 14

The international standard for science (the metric system)

Question 15

The density of water

Answer 15

1000 kg/m^3

Question 16

An equation that is dimensionally homogenous

Answer 16

An equation that is describing a physical relation that has the same dimensions on both sides of the equal sign.

Question 17

What are the 3 modes of energy exchange?

Answer 17

1. Latent heat
2. Sensible heat
3. Electromagnetic radiation

Question 18

What is an f(x) of the weight of the overlying atmosphere?

Answer 18

Pressure

Question 19

Saturation vapor pressure e^*

Answer 19

The maximum vapor pressure, the greatest amount of water that the atmosphere can hold. Can be estimated as an f(x) of temperature.

Question 20

Equation for e*

Answer 20

611 * exp(17.27*T / T- 273.3) (For a horizontal liquid surface)

Question 21

Estimate of the atmospheric pressure

Answer 21

1000 mb

Question 22

Amount of water vapor in percentage of total atmospheric volume

Answer 22

0-4%

Question 23

Range of vapor pressure in mb

Answer 23

0-40mb

Question 24

Saturation

Answer 24

Condition where air is holding as much water as possible. At maximum capacity, it precipitates. Changes with temperature and pressure.

Question 25

Absolute humidity

Answer 25

Ratio of mass H20/volume of air (in g/m^3).

Question 26

Specific humidity

Answer 26

Ratio of mass H20/mass of total air (in g/kg)

Question 27

Specific humidity mixing ratio

Answer 27

Ratio of mass H20/mass of DRY air (in g/kg)

Question 28

Relative humidity

Answer 28

A ratio measuring the percentage of saturation of actual H20 vapor/maximum H20 vapor. Changes with temperature and pressure.

Question 29

What change in temperature leads to a lower relative humidity if all else remains constant?

Answer 29

An increase in temperature

Question 30

Dew point

Answer 30

The temperature to which air must cool for condensation to occur (saturation).

Question 31

Precipitable water

Answer 31

The amount of water vapor in a column of the atmosphere extending from surface to top of atmosphere. Dimensions are [L] and it represents the depth of water that would result from the complete condensation and precipitation of all water vapor above a particular location.

Question 32

Evaporation

Answer 32

The change of state from liquid to gas

Question 33

Transpiration

Answer 33

Vapor loss form stomata in plant leaves

Question 34

Evapotranspiration

Answer 34

Net transfer (loss) of water vapor from wet surfaces and vegetation into the atmosphere.

Question 35

Vapor exchange

Answer 35

Dry air of temperature Ta lies above a horizontal water surface with the temperature Ts. Some water molecules have sufficient energy to enter the air above. The number of those molecules increases as Ts increases.

Question 36

e(a)

Answer 36

A steady state vapor pressure at specific given wind and temperature conditions. And f(x) of Ta and wind speed.

Question 37

Evaporation rate is proportional to ______

Answer 37

e*s - ea

Question 38

Controlling factors for evapotranspiration

Answer 38

1. water 2. energy 3. vapor pressure 4. wind 5. vegetation

Question 39

If e*s > ea

Answer 39

Evaporation is occurring

Question 40

If e*s < ea

Answer 40

Water is condensing on the surface

Question 41

If e*s = ea

Answer 41

Neither condensation nor evaporation is occurring

Question 42

Latent Heat of vaporization

Answer 42

The quantity of heat energy that must be absorbed to break the hydrogen bonds when evaporation takes place. The same quantity is released when when bonds are reformed and condensation occurs.