Geographical Techniques Questions and Answers

Answer: D

The dot and sphere method is best suited to show the distribution of population with a rural component and urban centres of different sizes. Dots show the rural population, with each dot standing for a fixed number of people, and spheres, drawn with volume in proportion to population, show the towns and cities.

A uniform dot method cannot show large urban centres well, and a multiple dot method uses dots of different value but still crowds large cities. The dot and circle method uses flat circles, which cannot show the great range in city size as well as spheres.

Answer: D

The altitudes are: Landsat V about 705 km (ii), IRS about 904 km (iii), SPOT about 832 km (i) and IKONOS about 681 km (iv). This gives the code ii, iii, i, iv.

The code ii, iv, i, iii gives IKONOS 904 km and IRS 681 km, which is wrong. The code iv, i, ii, iii gives Landsat 681 km, and the code iv, ii, iii, i puts SPOT at 904 km, so both fail. Landsat and SPOT are fixed by 705 and 832 km, so only one code works.

Answer: B

Nearest neighbour analysis was evolved by Clark and Evans, in 1954. It compares the observed mean distance between each point and its nearest neighbour with the distance expected for a random pattern, and the ratio shows whether the points are clustered, random or regular.

Zipf is known for the rank-size rule of cities. Carl Pearson devised the product moment correlation coefficient. The name Henry and Raize does not belong to this technique.

Answer: A

The spatial resolution of the LISS IV sensor on the Indian remote sensing satellite Resourcesat-1 (IRS-P6) is 5.8 m, in the multispectral mode.

The 23.5 m value is that of the LISS III sensor, and the coarser AWiFS has about 56 m. The 2.0 m and 10.0 m figures are not the resolution of LISS IV, so only 5.8 m is right.

Answer: B

A map of representative fraction 1 to 2,500 that is enlarged two and a half times has a scale of 1 to 1,000. Enlargement makes the scale larger, so the denominator becomes smaller:

\[ \frac{1}{2500} \times 2.5 = \frac{2.5}{2500} \]

\[ \frac{2.5}{2500} = \frac{1}{1000} \]

The scales 1 to 6,250 and 1 to 12,500 are larger denominators, which would be reduction, found by multiplying 2,500 by 2.5 or by 5, and 1 to 10,000 is a four-fold reduction. Option B is correct.

Answer: B

Population density is usually shown by the choropleth method. Density is a ratio for an area, so it is shown by shading the administrative areas in classes, darker for higher density. The isopleth method uses lines joining points of equal value, for example for temperature, and is used when the data vary continuously. The chorochromatic method shows the kinds of an area by colours, and the decimetric method is not a standard mapping method. Option B is correct.

Answer: D

A value of the nearest neighbour index Rn of 2.14 means that the settlement pattern is perfectly uniform. The index runs from 0, in which all the settlements are clustered at one point, through 1, for a random pattern, to 2.15, for a perfectly uniform pattern, which is a hexagonal lattice. A value of 2.14 is very close to the upper limit, so the pattern is uniform. Values near 0 would be a perfect cluster, and 1 would be random. Option D is correct.

Answer: D

Both the statements are wrong. It is active remote sensing systems that have their own source of energy, such as radar and lidar, which send out a signal and record what returns. Passive systems depend on solar energy, or on the energy that objects emit themselves, as with a camera or a scanner on a satellite recording reflected sunlight. The assertion and the reason have the two types the wrong way round, so both are false. Option D is correct.

Answer: C

The satellite image shown in television weather reports clearly depicts clouds and snow cover. The pictures are taken in visible and infrared light, in which clouds are bright and moving cloud patterns can be followed, and areas of snow also stand out. Temperature, rainfall, pressure, wind, humidity and fog are not seen directly in such images; they are worked out from other instruments and then shown on the charts. Option C is correct.

Answer: B

The matching is a-ii, b-iii, c-i, d-iv. Landsat V orbits at about 705 km. The Indian Remote Sensing satellites orbit at about 904 km. SPOT is at about 832 km, and IKONOS at about 681 km. A lower orbit gives a finer view of a narrower strip of ground and a higher one a wider view, so the altitude is matched to the purpose of each system. That order, ii, iii, i, iv, is option B. The other codes swap at least two of the altitudes, such as giving 681 km to Landsat or 832 km to IRS.