rivers

Question 1

title

Answer 1

an investigation into how river characteristics change with distance downstream in debden brook

Question 2

aim

Answer 2

to investigate how width, depth, and velocity changes with distance downstream in debden brook

Question 3

hypothesis

Answer 3

with distance from a river source, velocity will increase due to an increase in cross-sectional area, and reduction in friction

Question 4

Explain quantitative method

Answer 4

measuring velocity:
• metre stick, stopwatch, cork
• stick placed on surface, parallel to banks
• cork dropped half a metre upstream, to ensure it reaches optimum speed
• start/stop time at beginning/end
• picked up by awaiting person to prevent littering
• repeated 5 times to get average

Question 5

explain qualitative method

Answer 5

field sketch:
• stood on bank to observe course & surroundings
• drew general shape, width, and surrounding vegetation
• smaller details e.g housing, storm drains, large roots, slip off slopes, river cliffs, were added
• direction of flow, width measurement, weather, season annotated
• compass arrows added
• date and time added

Question 6

three risks and general description

Answer 6

• tics can cause lyme disease
-insect repellent
• wet ground can cause slipping
-appropriate footwear, avoid areas
• water can cause drowning
-sensible, stay in groups
• microbes can cause weils disease
-dont drink/splash

Question 7

my result

Answer 7

steep rise from site 1 to site 2, then sugnificantly decreased at site 3 (anomaly)
width and depth data fit bradshaw model, velocity did not

Question 8

why was site 3 an anomaly

Answer 8

man made bridge next to site:
-acted as artificial dam, preventing flow
-sediment from construction could have been suspended in river, creating friction

Question 9

faults in measuring width/depth

Answer 9

• difficulty holding tape measure straight in flowing water
• hard to tell exactly where river edge was
• rocks/obstacles could have obstructed depth
• worn metre sticks

Question 10

faults in measuring velocity

Answer 10

• 25 children stood in river - creates friction and slows velocity
• cork could be aided by wind
• surface is slower than middle of channel
• human error
• only 5 for an average

Question 11

why was this a suitable topic for enquiry?

Answer 11

already an accepted model, the Bradshaw Model, to compare with

river characteristics are also on gcse syllabus

Question 12

advantages of location

Answer 12

• quick access to all three courses, meaning data recorded on same day
• small and shallow enough for safe and accessible entry
• 30 mins from school

Question 13

explain theory investigated

Answer 13

investigate the Bradshaw Model, which illustrates how velocity, depth and width will increase, and load size and channel slope will decrease
model is easy to read

Question 14

how did hypothesis link to aim

Answer 14

aim was (……). for our hypothesis we made a positive statement to cover this (……)

Question 15

justify choice of sampling strategy

Answer 15

stratified
-all three courses were recorded
-safe and accessible
-large opening for many students

Question 16

assess how effective data presentation technique was

Answer 16

line graph was mostly effective
-easy to draw
-accurate, using graph paper
-easy to read, clear & simple
-all three sites recorded on same graph as continuous data
-only inaccuracy came from data itself