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MODUL • Fizik TINGKATAN 5

Latihan / Exercise
1 Seorang pelajar menggetarkan suatu sistem getaran spring 4 Rajah menunjukkan gelombang bunyi yang dihasilkan
sebanyak 4 kali per saat. Panjang gelombang bagi spring daripada satu tala bunyi.
tersebut ialah 0.6 m. Berapakah halaju gelombang menerusi The diagram below shows the sound waves produced by a
spring tersebut? KBAT tuning fork. 4 cm
A student makes a spring vibrating system vibrate at 4 times
per second. The wavelength of the wave on the spring is
0.6 m. What is the speed of the wave moving along the spring?
Penyelesaian / Solution
Diberi / Given
f = 4 Hz, λ = 0.6 m 150 cm
v = fλ

= 4 Hz × 0.6 m UNIT 1
= 2.4 m s –1
(a) Berdasarkan rajah, tentukan
Based on the diagram, determine
2 Gelombang radio merambat dengan halaju (i) amplitud / the amplitude
3 × 10 m s . Berapakah panjang gelombang bagi (ii) panjang gelombang / the wavelength
8
–1
gelombang radio FM yang diterima pada 200 MHz bagi (b) Berapakah frekuensi gelombang bunyi sekiranya
mendapatkan siaran radio tersebut? halaju bunyi adalah 330 m s ?
–1
Radio waves travel at a speed of 3 × 10 m s . What is the What is the frequency of the sound waves if the speed of
–1
8
wavelength of FM radio waves received at 200 MHz on your sound is 330 m s ?
–1
radio dial? Penyelesaian / Solution
Penyelesaian / Solution 4 cm

Diberi / Given (a) (i) a = 2 (b) v = fλ
–1
v = 3 × 10 m s , f = 200 MHz = 2 cm 330 m s = f × 0.5 m
8
–1
.
. .
v = fλ f = 660 Hz

8
–1
6
(3 × 10 m s ) = (200 × 10 Hz) × λ (ii) 3λ = 150 cm
λ = 1.5 m λ = 50 cm
3 Seutas tali direntangkan di atas lantai. Satu penghujung 5 Rajah di bawah menunjukkan graf sesaran-jarak.
tali tersebut digoyangkan dengan frekuensi 8 Hz. Graf di The diagram below shows the displacement-time graph.
bawah menunjukkan sebahagian pergerakan tali dalam Sesaran / m
suatu masa. Displacement / m
A long rope is stretched out on the floor. One end of the rope 10
is then shaken at frequency of 8 Hz. The graph below shows
the rope at a particular moment in time. 0 Masa / s
Sesaran / m 0.2 0.4 0.6 0.8 Time / s
Displacement / m –10
0.5
Berdasarkan graf di atas, tentukan
0 Jarak / m Based on the graph above, determine the
0.4 0.8 1.2 1.6 Distance / m (a) amplitud / amplitude
–0.5 (b) tempoh / period
(c) frekuensi / frequency
Tentukan / Determine Penyelesaian / Solution
(a) amplitud / the amplitude (a) a = 10 m
(b) panjang gelombang / the wavelength (b) T = 0.4 s
(c) halaju gelombang / the speed
Penyelesaian / Solution (c) f = 1
(a) a = 0.5 m T 1
(b) λ = 0.8 m = 0.4 s
(c) v = fλ

= 8 Hz × 0.8 m = 2.5 Hz
= 6.4 m s –1

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