Geographical investigation

Question 1

Defining systematic sampling

Answer 1

Collection of data from regular intervals.

E.g (time intervals, distance intervals, people)

Question 2

What are the pros and cons of systematic sampling

Answer 2

Pros:

1. Ensures that the population would be evenly sampled.
2. Convenient

Cons:

1. Might obtain biased information which is not an accurate representation of the data.
2. Potentially miss out data varioations.

Question 3

Define random sampling

Answer 3

Collection of data such that every member has an equal chance of being selected.

Question 4

What are the pros and cons of random sampling

Answer 4

Pros:
1. Allows everyone to have an equal chance of being selected

Cons:
1. Doesn’t represent the whole population

Question 5

What do you use to measure wind speed.

What are some measures you have to take to get accurate results

How do you know the results

What is the significance of the results

Answer 5

Anemometer

Use anemometer in an open area where the wind flows freely

Results of windspeed shown on display

Question 6

What do you use to measure wind direction

What are some precautions to take?

Reading of the instrument.

Answer 6

Wind vane

1. Ensure that it is being used in an open area where wind is blowing directly at it
2. Hold it away from you slightly above the head
3. Ensure that the wind vane is not obstructed

Record the direction the wind vane points to as that is the direction the wind is coming from.

Question 7

Recording wind and frequency

Answer 7

Use a wind rose.

Question 8

What do you use to measure temperature

What are some precautions to take to ensure accurate results

What determines the reading in the instrument.

Answer 8

1. Analogue thermometer
2. Digital thermometer
3. Maximum and minimum thermometer

Place the maximum and minimum thermometer in a Stevenson screen so that it is kept out of direct sunlight

Place it 1.5 meters above the ground so that it does not absorb heat from the ground and obtain inaccurate readings of the temperature.

The bottom of the metal index represents the temperature reading.

Question 9

What instrument do we use for relative humidity.

What precautions do we take for accurate results

Significance of readings

Answer 9

Sling psychrometer

(Precautions)
Swing the sling psychrometer at a comfortable and steady pace and far from the body so that it doesn’t pick up the body heat.

(Significance of readings)
Large wet bulb depression = lot of water evaporated = Low humidity

Small wet bulb depression = less water evaporated = high humidity

No wet bulb depression = no water evaporated = relative humidity is at 100%

Question 10

What instrument do we use for measuring precipitation

What precautions do we have to take for accurate readings. .

Significance of readings

Answer 10

Rain gauge

(Precautions)
1. Make sure that the rain gauge is placed in an open area with no buildings so that the rain wont be intercepted by these objects.

2. Place the rain gauge protected from the wind so that the wind won’t blow the rain away which leads to an underestimation of the rainfall.
3. Prevent the rain gauge from falling by sinking it into the ground with about 30cm protruding out.
4. Place the rain gauge on softer ground so that water doesn’t splash.

(Significance of readings)
0.5mm= minor rainfall
>5mm = thunderstorm