Map scale and measuring distance
A map's scale compares map distance to real ground distance, usually as a representative fraction (RF) such as 1:50,000 -- 1 cm on the map is 50,000 cm (0.5 km) on the ground. To find a ground distance, measure the map distance in cm, multiply by the scale number, then convert to m or km. A straight-line distance is measured with a ruler; a curved route must be followed bend by bend with thread or a marked paper strip, since a straight line under-measures it.
Grid references: eastings then northings
Topographic maps carry a numbered grid: eastings run up the map, numbered west to east; northings run across, numbered south to north. The rule is "along the corridor, then up the stairs" -- read the easting first, then the northing. A four-figure grid reference names a whole square, using the easting then northing of its south-west corner. A six-figure reference pinpoints a spot inside it: add tenths across (after the easting) and tenths up (after the northing), e.g. 427174.
Contours, gradient and cross-sections
Contour lines join points of equal height, at a fixed interval (e.g. 20 m). Close together means a steep slope; far apart means gentle. A spot height marks one exact height. Gradient is written "1 in n", n = horizontal distance / vertical height -- a SMALLER n is steeper, a LARGER n gentler. A cross-section turns the pattern along a line into a side-on profile: read the height at each contour crossing, plot height against distance, then join with a smooth ruled line.
Drawn from real examiner reports.
Six-figure grid reference errors
Six-figure grid references are a consistently weak skill. Common errors: giving the northing before the easting, mismeasuring the third or sixth digit (the tenths across or up), and guessing instead of measuring. Lay a ruler along the bottom edge for the tenths across, then up the left edge for the tenths up -- never estimate by eye.
(s23 P21/22/23 Q1b)
Curved routes and scale slips
Two distance errors recur together. First, measuring a curved route with a straight ruler, which always UNDER-measures -- follow it bend by bend with thread or a marked paper strip. Second, a scale slip (not multiplying by the full scale number, or misplacing a decimal) can put the answer out tenfold. Always write map cm x scale number = ground cm, then convert.
(s23 P21 Q1b(i))
Bearings: measure clockwise from north
Bearings recur as a weak area. A bearing is always measured CLOCKWISE from north (000 degrees) as a three-figure number (045, not 45). Common errors: measuring anticlockwise, misaligning the protractor, and -- when a compass DIRECTION is asked -- giving an 8-point answer (south-east) where the 16-point answer (south-south-east) is required.
(w23 P22 Q1b)
Cross-section completion errors
Constructing a cross-section is an easy-marks task candidates repeatedly spoil. Common errors: plotting a crossing at the wrong height, transposing labelled features, drawing freehand, and omitting the connecting line so points are left unjoined. Read each height where the line crosses a contour, plot every point at its correct distance, then join with one smooth line.
(s23 P21/22/23 Q1c-d)
Four-figure vs six-figure grid reference
Do not confuse what each grid reference locates. A four-figure reference (e.g. 4217) names a WHOLE grid square -- the easting then northing of its south-west corner. A six-figure reference (e.g. 427174) pinpoints a POINT inside that square, adding a tenth across then a tenth up. Giving four figures where a precise point is asked for does not answer the question.
Grid references have a fixed reading order
A testable wrong belief: that a grid reference can be read in whichever order feels natural. On an Ordnance-Survey-style map the order is fixed -- "along the corridor, then up the stairs": the easting (across, along the bottom) comes first, then the northing (up the side). Swapping the order gives a different, wrong location, even if every digit is correct.
(s23 P21/22/23 Q1b)
A bigger "n" is not a steeper slope
A common, testable inversion. A gradient "1 in n" means a rise of 1 unit for every n units travelled horizontally. A SMALL n (1 in 5) spreads the gain over a short distance, so the slope is STEEP; a LARGE n (1 in 200) spreads it over a much longer distance, so it is GENTLE. Candidates often assume "bigger number = steeper", the exact opposite -- the SMALLER n is steeper.
(general exam skill)
Describe distribution: three elements
"Describe the distribution/relief/site" is often answered as "where ONE feature is". A full answer needs THREE elements: a compass direction (not "near"), a scale-based distance ("2 km from"), and a reference to another feature. Describe the whole pattern, not one point.
Quote exact figures, not "about"
Examiners mark down vague quantity words -- "about", "nearly", "majority" (for a value under 50%) -- in favour of an exact figure with its unit. Where you can read or calculate a precise number, quote it (km, m, degrees, %) rather than a vague word.
Measure with ruler and protractor
Most Paper 2 map answers are measured, not guessed. Use a ruler for distances and grid-reference tenths, a protractor for bearings, and a ruler to plot a cross-section. Guessing "by eye" is where marks are lost -- treat every distance, reference and bearing as a measurement.
Describe vs explain vs compare
Match the command word. "Describe" wants WHAT a pattern, relief or site IS. "Explain" wants WHY. "Compare" needs linking words (higher/lower, steeper/gentler), not two separate descriptions. Answering "describe" with reasons, or "compare" as unlinked descriptions, loses marks.
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