Hydrology Objectives

Question 1

Science which deals with the occurrence, distribution, and disposal of water on the planet earth

Answer 1

Hydrology

Question 2

study the process of hydrological cycle, which occurs in atmosphere like evaporation, precipitation and condensation and in ground like surface runoff, rainfall, infiltration along with their interactions. (Atmosphere + earth)

Answer 2

Hydrometeorology

Question 3

Study of solid earth

Answer 3

Geology

Question 4

study of groundwater – it is sometimes referred to as geohydrology or groundwater hydrology.

Answer 4

Hydrogeology

Question 5

It is a vertical and horizontal movement of water as either vapor, liquid, or solid between the earth’s surface, subsurface, atmosphere, and oceans

Answer 5

Water cycle, water transfer cycle or hydrologic cycle

Question 6

Lateral movement of water in the soil

Answer 6

Seepage

Question 7

Vertical movement of water in the soil

Answer 7

Percolation

Question 8

Entry of water into soil surface

Answer 8

Infiltration

Question 9

Water flowing towards lake, river, oceans as surface or subsurface

Answer 9

Runoff

Question 10

amount of water in a reservoir divided by either the rate of addition of water to the reservoir(inflow) or the rate of loss from it(outflow).

Answer 10

Residence time or retention time

Question 11

measure of how long a substance or material remains in a particular system or environment.

Answer 11

Residence time or retention time

Question 12

What is the Residence time of atmospheric water in the phases of water cycle

Answer 12

9 days

Question 13

What is the Residence time of biological water(plants )in the phases of water cycle

Answer 13

1 week

Question 14

What is the Residence time of rivers and steams in the phases of water cycle

Answer 14

2-6months

Question 15

What is the Residence time of ocean in the phases of water cycle

Answer 15

3200 years

Question 16

What is the Residence time of ground water in the phases of water cycle

Answer 16

Up to 10,000 years

Question 17

In which phase in the hydrologic cycle has the highest residence time of water.
A. Antarctic ice
B. Groundwater:deep
C. Glaciers
D. Ocean
E. Atmospheric water

Answer 17

B. Groundwater:deep

Question 18

Percentage of water in the world that is saline is about

Answer 18

97%

Question 19

Percentage of Earth covered by oceans

Answer 19

71%

Question 20

An area that topographically appears to contribute all the water that passes through specified cross section of a stream (the outlet).
A. Watershed
B. Catchment area
C. Drainage basin
D. River basin
E. All of the above

Answer 20

E. All of the above

• “watershed”, “catchment area”, “drainage basin”, and “river basin” all refer to the same concept - the area of land that contributes water to a specific point or outlet of a stream or river.

Question 21

The boundary line along topographic ridges that separates two adjacent watershed

Answer 21

Watershed divide or watershed boundary

Question 22

These are stream that flows into a larger stream or other body of water

Answer 22

Tributaries

Question 23

• first order streams
• smallest streams at the outer limits of a watershed

Answer 23

Head water

Question 24

Single point or location at which all surface drainage from a basin comes together or concentrates as outflow from the basin in the stream channel

Answer 24

Outlet

Question 25

Portion of the precipitation that makes way towards stream channels, lakes, oceans as surface or subsurface

Answer 25

Runoff

Question 26

Baseflow is also called as

Answer 26

Groundwater flow

Question 27

It provides the relationship between stream stage and discharge

Answer 27

Rating curve

Question 28

Height of water level in a stream

Answer 28

Stage

Question 29

Graphical representation of runoff rate over time

Answer 29

Hydrograph

Question 30

Graph of 1 unit direct runoff vs. time

Answer 30

Unit hydrograph

Question 31

It is the time from the beginning of the rising limb to the occurrence of the peak discharge

Answer 31

Time to peak

Question 32

It is the time required for water to travel from the most hydraulically remote point in the basin to the basin outlet.

Answer 32

Time of concentration

Question 33

It is the time between the center of mass of the effective rainfall hyetograph and the center of mass of the direct runoff hydrograph

Answer 33

Lag time

Question 34

It is the duration of the direct runoff hydrograph

Answer 34

Time base

Question 35

Effective rainfall is also known as

Answer 35

Excess rainfall

Question 36

Amount of rainfall that becomes the direct runoff at the watershed outlet

Answer 36

Excess rainfall or effective rainfall

Question 37

Result of the total or gross rainfall after losses(infiltration and absorb by the soil and rainfall stored in depressions) are deducted

Answer 37

Excess rainfall or effective rainfall

Question 38

Hydrograph was made of

Answer 38

Overland flow, interflow, and baseflow

Question 39

Direct runoff hydrograph from a unit excess precipitation that occurs uniformly over a basin

Answer 39

Unit hydrograph

Question 40

A chart or function describing the temporal distribution of precipitation during a storm event, at a point or over an area

Answer 40

Hyetograph

Question 41

The science and practice of water flow measurement

Answer 41

Hydrometry

Question 42

Measurement of the elevation and depth of features of the earth’s surface

Answer 42

Hypsometry

Question 43

Control structures in canals or streams

Answer 43

Weirs

Question 44

The following is not a direct stream flow determination technique A. Dilution method B. Ultrasonic method C. Area-velocity method D. Slope-area method E. None of the above

Answer 44

D. Slope area method

Question 45

Direct runoff is composed of

Answer 45

Surface runoff Prompt interflow Channel precipitation

Question 46

The term base flow denotes A. Delayed groundwater flow reaching a stream B. Delayed groundwater flow and snowmelt reaching a stream C. Delayed groundwater and interflow E. None of the above

Answer 46

A. Delayed groundwater flow reaching a stream

Question 47

A stream that carries water a considerable portion of the time, but that ceases to flow occasionally or seasonally because bed seepage and evapotranspiration exceed the available water supply

Answer 47

Intermittent stream

Question 48

A stream channel that carries water only during and immediately after periods of rainfall or snowmelt

Answer 48

Ephemeral stream

Question 49

A stream that contains water at all times except during extreme drought

Answer 49

Perennial stream

Question 50

An intermittent stream A. Has water table above the stream bed through out the year B. Has only flash flows in response to storms C. Has flows in the stream during wet season due to contribution of groundwater D. Does not have any contribution of groundwater at any time E. None of the above

Answer 50

C. Has flows in the stream during wet season due to contribution of groundwater

Question 51

In a watershed, A. Faster peak flows occur in flat watershed than in steep watershed B. Faster time to peak flows occur in an elongated watershed than circular watershed C. Longer time to peak flows occur in watershed with dense drainage than in less dense drainage D. Larger watershed produces larger runoff than smaller watershed E. Storm moving towards upstream produces larger streamflow and shorter time to peak than storm moving towards downstream

Answer 51

D. Larger watershed produces larger runoff than smaller watershed

Question 52

In the hydrological cycle the average residence time of water in the global a. Atmospheric moisture is larger than that in global rivers b. Oceans is smaller than that of the global groundwater c. Rivers is larger than that of the global groundwater d. Oceans is larger than that of the global ground water

Answer 52

b. Oceans is smaller than that of the global groundwater

Question 53

A graduated scale placed in a position so that the stage of a stream may be read directly therefrom. a. Staff gauge b. Current meter c. Wire-weight gauge d. Measuring stick e. None of the above

Answer 53

a. Staff gauge

Question 54

Unit hydrograph is made of

Answer 54

Direct runoff only

Question 55

For a given storm, assuming other factors remain constant a. Basin having low drainage density give smaller peaks in flood hydrograph b. Basin with large drainage densities give smaller flood peaks c. Low drainage density basins give shorter time bases of hydrograph d. Flood peak is independent of the drainage density e. Large drainage density basins produce longer time bases of hydrograph

Answer 55

a. Basin having low drainage density give smaller peaks in flood hydrograph

Question 56

A unit hydrograph has one unit of

Answer 56

Direct runoff