1. State whether the following statements are True or False:

The rate of decrease of temperature of dry air in troposphere is approximately 5·6°C/km.

The standard raingauge used in India has collecting area of diameter =20 cms.

Interflow is amount of rainfall which contributes to the groundwater (aquifer).

Double mass curve is used to compute average rainfall over an area.

A unit hydrograph has unit depth of direct surface runoff.

W-index and cj)-index vary from storm to storm.

Dilution technique is used for silt measurement in river water.

Draw a self-explanatory block diagram representing the hydrologic system.

Explain the formation of precipitation and various forms of precipitation.

The isohyets due to a storm in a catchment have the following data. Estimate the mean precipitation due to the storm.

Isohyets Area
12 60
12-10 140
10-8 100
8-6 80
6-4 20

Describe the procedure to estimate the water equivalent of a given snowfall.

4. Define the following terms

Interception

Evapotranspiration

Infiltration

Double mass curve

Pan coefficient

Interflow

Direct runoff

Explain the evaporation. various factors affecting

Draw a neat sketch with dimensions of the lSI modified Class-A Pan and explain the procedure for measurement of evaporation.

Enumerate the Direct and Indirect determination of discharge.

Explain the Slope-Area method of discharge measurement.

Give steps involved in derivation of a Unit Hydrograph from a Storm Hydrograph.

Given the ordinates of a 4-h Unit Hydrograph as below. Derive the ordinates of a 12-h Unit Hydrograph for the same catchment.

Time 12, 16, 20, 24, 28, 32, 36, 40, 44
Ordinate of4-h UH 20, 80, 130,150,130,90, 52, 27, 15,