Geography EQ 1 (Coast) Part 2

Question 1

detailed way of how a wave is formed

Answer 1

Ocean waves form when winds blow over the surface of the ocean. The friction from the wind causes the water particles near the surface to move in an orbit i.e., in a circular motion, which creates the waves.

Question 2

what is the crest

Answer 2

higehst part of wave

Question 2

what are the 6 parts of a wave?

Answer 2

1. crest
2. trough
3. Wave height
4. Wavelength
5. Wave steepness
6. Wave period
7. Wave frequency

Question 3

what is the trough

Answer 3

lowest part of wave

Question 4

what is the wave height

Answer 4

the vertical distance between the crest and the trough. (lowest point).

Question 5

what is a wavelength

Answer 5

the horizontal distance from crest to crest or from trough to trough.

Question 6

what is a wave period

Answer 6

the time waves take to travel through one wavelength (one crest to the next)

Question 6

what is wave steepness?

Answer 6

it is the ratio of wave height to wavelength (height / wavelength).

Question 7

what is wave frequency

Answer 7

the number of wave crests or troughs that pass a fixed point in one second.

Question 8

what are the 3 factors affectinge wave energy?

Answer 8

1. Wind speed: how fast the wind is blowing.
2. Wind duration: how long the wind blows.
3. Fetch is the distance the wind blows over the seas or oceans. The greater the fetch, the
   more energy the waves have.

Question 9

what is wind speed ( in terms of how it affects wave energy)

Answer 9

how fast the wind is blowing.

Question 10

wind duration ( in terms of how it affects wave energy)

Answer 10

how long the wind blows.

Question 10

what happens to waves as they approcach the shore?

this is a 5 step answer!

Answer 10

1. As waves approach the coastline, water gets shallower.
2. Friction between water particles and the sea bed causes the base of the wave to slow down.
3. Wave height increases and wavelength decreases, making waves steeper and closer together.
4. The wave crest eventually topples over, causing the wave to break onto the coast.
5. This releases the energy of the wave.

Question 11

fetch ( in terms of how it affects wave energy)

Answer 11

Fetch is the distance the wind blows over the seas or oceans. The greater the fetch, the more energy the waves have.

Question 12

what happens when wave enrgy is high??

Answer 12

The higher the wave energy is, the steeper the wave, and the shorter the wave period becomes.

Question 13

describe characteristics of Waves in the open ocean there are 3!

Answer 13

Have a long wavelength.
Have a low wave height.
Water particles move in an orbit.

Question 14

define swash.

Answer 14

The water rushes up the slope of the shore as a swash. As swash moves up the beach, it carries sediments with it.

Question 15

define backwash

Answer 15

Swash loses energy due to gravity and friction with the land and returns to the sea as backwash. The backwash carries sediments from the shore into the sea.

Question 16

2 types of waves

Answer 16

1. constructive
2. destrcutive

Question 17

constructive waves characeteritics:
Beach Gradient
Wave Height
Wave Length
Wave Frequency
Wave Period
Swash & Backwash
Energy
Dominant Process

Answer 17

Gentle gradient
Low wave height (<1m)
Long wavelength (up to 100m)
Low frequency (6-9 per minute)
High period (one every 8-10 seconds)
Swash more powerful than backwash
Low-energy waves
Deposition process more prominent

Question 18

destructive waves characteristics
Beach Gradient
Wave Height
Wave Length
Wave Frequency
Wave Period
Swash & Backwash
Energy
Dominant Process

Answer 18

Steep gradient
High wave height (>1m)
Short wavelength (<20m)
High frequency (10-15 per minute)
Low period (one every 5-6 seconds)
Backwash more powerful than swash
High-energy waves
Erosion process more prominent

Question 19

what is abrasion

Answer 19

1. Sediments carried by waves (sand and rocks) are hurled against the coast as waves break.
2. These sediments knock and scrape against the coastal cliffs.
3. This weakens the surface and breaks down the coast.
4. Over time, the impact is powerful enough to undercut a cliff.

Question 19

what is hydraulic action?

Answer 19

1. Waves break against a rock surface due to their sheer weight and power.
2. Waves trap air in cracks in the rocks.
3. The air is compressed by the oncoming waves, exerting pressure on the cracks.
4. Repeated compression of the air weakens the rock.
5. The rock eventually breaks apart.

Question 20

what is attrition

Answer 20

1. Rock particles carried by waves rub or hit against one another.
2. They break down into smaller pieces.
3. The particles become smoother and more rounded over time.

Question 20

what are the 4 types of erosion?

Answer 20

1. hydralic action
2. abrasion
3. attrition
4. solution

Question 21

what is solution

Answer 21

1. Sea water reacts chemically with water-soluble minerals in coastal rocks and dissolves them.
2. When solution of minerals occurs, rocks are weakened.
3. Eventually, the rocks disintegrate.

Question 22

define longshore drift

Answer 22

• The longshore current flows parallel to the coast, and is generated by winds, tides and waves approaching at an angle.
• longshore current plays transporte materials along the coast.

Question 22

how is longshore drift formed

Answer 22

1. The swash moves sediments up onto the coast at an angle.
2. The backwash returns sediments to the sea at right angles due to gravity.
3. This creates a zig-zag movement of sediments along the coast.
4. This process of sediment movement parallel to the coast is called longshore drift.

Question 22

when does deposition occur?

Answer 22

Deposition occurs when waves lay down sediments along the coast. When small or low- energy waves do not have the energy to carry the load, deposition occurs.

Question 22

which is deposted first? larger or smaller sediments?

Answer 22

Larger sediments are deposited
first, followed by smaller sediments.