6A10m - Pembelauan air di pantai nelayan

7.  Diagram 7 shows a pattern of waves form a ripple tank.
Rajah 7 menunjukkan corak gelombang daripada satu tangki riak.

(a) Name the phenomenon shown in Diagram 7.1.
Namakan fenomena yang ditunjukkan dalam Rajah 7.1
……………………………………………………………………………………………………

[1 mark / 1 markah]

(b) What will happen to the following when a wave undergoes the phenomenon
mentioned in 7(a)?
Apakah yang akan berlaku terhadap suatu gelombang yang mengalami fenomena yang disebutkan dalam 7(a)?

(i) Speed:
Kelajuan
………………………………………………………………………………………….

(ii) Amplitude:
Amplitud
…………………………………………………………………………………………..

[2marks / 2 markah]

(c) State the effect of decreasing the width of slit on the wave pattern in Diagram 7.1
Nyatakan kesan terhadap corak gelombang dalam Rajah 7.1 jika mengurangkan kelebaran celah itu.

…………………………………………………………………………………………………….

[1 mark / 1 markah]

(d) Diagram 7.2 shows a village near a beach with bay and cape. During rainy season, waves are big. The waves eroded the seashore, caused the jetty to collapse and damage the boats.
Rajah 7.2 menunjukkan sebuah kampung berhampiran pantai yang berteluk dan bertanjung.Semasa musim tengkujuh, saiz ombak adalah besar.Ombak besar telah menyebabkan hakisan pantai, keruntuhan jeti dan kerosakan bot penduduk tempatan.

To prevent similar damage in future, the villagers suggest building retaining walls and relocating the jetty. Based on the situation, make suggestions of ways to help the villagers by using the following aspects and your reason.
Bagi mengelakkan kerosakan serupa berulang para penduduk bercadang untuk membina benteng dan memindahkan jeti ke tempat baru.Berdasarkan situasi tersebut, berikan cadangan untuk mengatasi masalah penduduk dengan menggunakan aspek-aspek berikut dan jelaskan sebabnya.

(i) Structure of retaining wall
Struktur benteng

…………………………………………………………………………………
Reason
Sebab:
…………………………………………………………………………….

[2marks / 2 markah]

(ii) Gap design
Pintu masuk

………………………………………………………………………………..
Reason
Sebab:
………………………………………………………………………………..

[2marks / 2 markah]

(iii) The location of new jetty
Lokasi baru jeti

………………………………………………………………………………………
Reason
Sebab:
……………………………………………………………………………….

[2marks / 2 markah]

Jawapan :

No		Answer	Marks
7	a	Diffraction	1
	b(i)	speed unchange	1
	(ii)	Amplitude decrease	1
	c.	Bending more / become circular / spreading more	1
	d(i)	retaining wall made of concrete /high strength material/stronger/slope design able to withstand impact of the wave/difficult to break/long lasting	1 1
	(ii)	Small gap More diffraction occurs / reduce wave amplitude/reduce wave energy	1 1
		jetty new location at bay the wave in the bay is calmer than cape region/boat safety	1 1
TOTAL			10