Page 103 - Hybrid PBD KSSM 2021 Tg 4 - Fizik

Fizik Tingkatan 4 Bab 2
FOKUS KBAT

Raqib dan Amir merupakan pelari terakhir dalam acara 4 x 100 m bagi dua TIP Menjawab
pasukan yang berbeza. Semasa Raqib memulakan lariannya, Amir sudah berada
20 meter di hadapannya dan sedang berlari dengan halaju seragam 7.2 m s . Bandingkan masa kedua-dua
–1
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Raqib and Amir were the last runner in the 4 x 100 m event for two different teams. When Raqib pelari menamatkan perlumbaan
started his run, Amir was already 20 metres in front of him and was running with a uniform velocity of bermula dari saat Raqib
7.2 m s . memulakan larian. Pelari yang
–1
mengambil masa yang lebih
Raqib memulakan larian dengan memecut 3 m s selama 4 saat dan kemudian singkat adalah pemenang.
–2
meneruskan larian dengan halaju seragam sehingga ke garisan penamat. Compare the time the two runners
Raqib starts the run by accelerating 3 m s for 4 seconds and then continue the run with uniform finished the race starting from the
–2
velocity all the way to the finish line. moment Raqib started the run. The
runner who takes the shorter time is
Siapakah yang terlebih dahulu tiba di garisan penamat? the winner.
Who arrives at the finish line first? KBAT Mengaplikasi KBAT Menganalisis
Larian Amir / Amir's run:
Masa menamatkan larian = sesaran = 100 – 20 = 11.11 s
halaju 7.2
displacement 100 – 20
Time to finish the run = velocity = 7.2 = 11.11 s

Larian Raqib (4 saat pertama) / Raqib's run (First 4 seconds):
v = u + at = 0 + (3)(4) = 12 m s –1
v = u + 2 as
2
2
12 = 0 + 2(3)s
2
2
s = 24 m
Larian Raqib (selepas 4 saat) / Raqib's run (after 4 seconds):

Masa / Time = sesaran / displacement = 100 – 24 = 6.83 s
halaju / velocity 12

Jumlah masa Raqib menamatkan larian / Total time Raqib finished the run
= 4 + 6.83 = 10.83 s

Pelari Jumlah masa menamatkan larian
Runner Total time to finish the run
Amir 11.11 s
Raqib 10.83 s

Oleh itu, Raqib terlebih dahulu tiba di garisan penamat berbanding Amir.
So, Raqib arrived at the finish line earlier than Amir.

© Penerbitan Pelangi Sdn. Bhd. 62

02 HYBRID PBD FIZIK F4.indd 62 05/11/2021 8:20 AM