SWS 3022 Exam 1 Exam Questions
with Answers
If point A in a soil has a total potential energy of -100 cm, and point B has a total
potential of -300 cm, and the distance between the points is 20 cm, and the hydraulic
conductivity is 2 cm/hr, what is the total flow, Q, between the points? - Answer-20 cm/hr
300-100 = 200/20 = 10*2 = 20
Two points in the soil are both exactly 10 cm below the soil surface and are 20 cm
apart. The capillary potential energy at point A is -200 cm and at point B it is -100 cm.
Will water flow between the points and, if so, in what direction? - Answer-Yes, from B to
A
Less Negative to More Negative
-100 to -200
Two points in the soil are both exactly 10 cm below the soil surface and are 20 cm
apart. The capillary potential energy at point A is -200 cm and at point B it is -100 cm.
What is the gradient between the two points? - Answer-5
200-100 = 100/20 = 5
Two points in the soil are both exactly 10 cm below the soil surface and are 20 cm
apart. The capillary potential energy at point A is -200 cm and at point B it is -100 cm. If
the hydraulic conductivity is 3 cm/hr what is the total flow between the points? - Answer-
15 cm/hr
200-100 = 100/20 = 5*3 = 15
It is possible to have a very large gradient, yet water will not flow between two points. (T
or F) - Answer-True
Hydraulic conductivity is independent of water content. (T or F) - Answer-False
Matric or capillary potential energy is always negative. (T or F) - Answer-True
Gravitational potential energy is dependent on soil texture. (T or F) - Answer-False
Plant available water is between saturation and permanent wilting point. (T or F) -
Answer-False
Hydrogen has no valence shell. (T or F) - Answer-False
In a water molecule, there is a slight partial negative charge near the oxygen atom and
a slight positive charge near the hydrogens. (T or F) - Answer-True
, Oxygen has 8 electrons in its valence shell. (T or F) - Answer-False
Water's polarity and consequent hydrogen bonding is ultimately responsible for many of
its unusual properties. (T or F) - Answer-True
Cohesion of water molecules in the liquid is due to hydrogen bonding. (T or F) - Answer-
True
The strength of capillary forces is inversely related to the radius of the pore space. (T or
F) - Answer-True
Soil structure has no influence on the strength of capillary forces. (T or F) - Answer-
False
The two forces responsible for capillarity in soils are adhesion and cohesion. (T or F) -
Answer-True
Oxygen has exceptionally high electronegativity. (T or F) - Answer-True
Soil bulk density has no influence on capillary forces. (T or F) - Answer-False
At saturation the capillary potential energy of a soil is zero. (T or F) - Answer-True
Atoms like oxygen "prefer" to have 8 electrons in their valence shells. (T or F) - Answer-
True
Water's polarity is ultimately the result of oxygen's high electronegativity. (T or F) -
Answer-True
Coarse-textured soils generally exert stronger capillary forces than do fine-textured
soils. (T or F) - Answer-False
Water is difficult to evaporate compared to other liquids. (T or F) - Answer-True
Hydraulic conductivity is the ease with which water moves through soil. (T or F) -
Answer-True
Potential energy is energy waiting to be used or exploited. (T or F) - Answer-True
Within a single water molecule hydrogen is bonded to oxygen by hydrogen bonding. (T
or F) - Answer-False
A saturated soil has zero capillary potential. (T or F) - Answer-True
Water moves in response to differences in potential energy. (T or F) - Answer-True
with Answers
If point A in a soil has a total potential energy of -100 cm, and point B has a total
potential of -300 cm, and the distance between the points is 20 cm, and the hydraulic
conductivity is 2 cm/hr, what is the total flow, Q, between the points? - Answer-20 cm/hr
300-100 = 200/20 = 10*2 = 20
Two points in the soil are both exactly 10 cm below the soil surface and are 20 cm
apart. The capillary potential energy at point A is -200 cm and at point B it is -100 cm.
Will water flow between the points and, if so, in what direction? - Answer-Yes, from B to
A
Less Negative to More Negative
-100 to -200
Two points in the soil are both exactly 10 cm below the soil surface and are 20 cm
apart. The capillary potential energy at point A is -200 cm and at point B it is -100 cm.
What is the gradient between the two points? - Answer-5
200-100 = 100/20 = 5
Two points in the soil are both exactly 10 cm below the soil surface and are 20 cm
apart. The capillary potential energy at point A is -200 cm and at point B it is -100 cm. If
the hydraulic conductivity is 3 cm/hr what is the total flow between the points? - Answer-
15 cm/hr
200-100 = 100/20 = 5*3 = 15
It is possible to have a very large gradient, yet water will not flow between two points. (T
or F) - Answer-True
Hydraulic conductivity is independent of water content. (T or F) - Answer-False
Matric or capillary potential energy is always negative. (T or F) - Answer-True
Gravitational potential energy is dependent on soil texture. (T or F) - Answer-False
Plant available water is between saturation and permanent wilting point. (T or F) -
Answer-False
Hydrogen has no valence shell. (T or F) - Answer-False
In a water molecule, there is a slight partial negative charge near the oxygen atom and
a slight positive charge near the hydrogens. (T or F) - Answer-True
, Oxygen has 8 electrons in its valence shell. (T or F) - Answer-False
Water's polarity and consequent hydrogen bonding is ultimately responsible for many of
its unusual properties. (T or F) - Answer-True
Cohesion of water molecules in the liquid is due to hydrogen bonding. (T or F) - Answer-
True
The strength of capillary forces is inversely related to the radius of the pore space. (T or
F) - Answer-True
Soil structure has no influence on the strength of capillary forces. (T or F) - Answer-
False
The two forces responsible for capillarity in soils are adhesion and cohesion. (T or F) -
Answer-True
Oxygen has exceptionally high electronegativity. (T or F) - Answer-True
Soil bulk density has no influence on capillary forces. (T or F) - Answer-False
At saturation the capillary potential energy of a soil is zero. (T or F) - Answer-True
Atoms like oxygen "prefer" to have 8 electrons in their valence shells. (T or F) - Answer-
True
Water's polarity is ultimately the result of oxygen's high electronegativity. (T or F) -
Answer-True
Coarse-textured soils generally exert stronger capillary forces than do fine-textured
soils. (T or F) - Answer-False
Water is difficult to evaporate compared to other liquids. (T or F) - Answer-True
Hydraulic conductivity is the ease with which water moves through soil. (T or F) -
Answer-True
Potential energy is energy waiting to be used or exploited. (T or F) - Answer-True
Within a single water molecule hydrogen is bonded to oxygen by hydrogen bonding. (T
or F) - Answer-False
A saturated soil has zero capillary potential. (T or F) - Answer-True
Water moves in response to differences in potential energy. (T or F) - Answer-True
