11.
You are a coach responsible to choose a student to join the school
basket ball team. A basic physical fitness test was carried out and the results
based on certain characteristics are as shown in table 11.1.
Anda
adalah seorang jurulatih yang ditugaskan untuk memilih seorang pelajar untuk
menjadi pemain bola keranjang sekolah. Satu ujian daya tenaga asas telah
dijalankan dan keputusannya berdasarkan ciri-ciri tertentu yang ditunjukkan
dalam jadual 11.1.
|
characteristics
Ciri
Students
Pelajar
|
Mass
Jisim
(kg)
|
Height
Tinggi
(m)
|
Responding time
Masa
Tindak balas (s)
|
Power ( Time taken
to transfer 50 bricks to a distance of 5 m)
Kuasa ( masa diambil untuk memindahkan 50 batu bata pada jarak 5m)
|
Time taken to
complete 100m run.
Masa
Larian 100m (s)
|
|
A
|
70
|
1.30
|
0.01
|
4 minutes
/ minit
|
11.0
|
|
B
|
65
|
1.50
|
0.20
|
3 minutes / minit
|
10.6
|
|
C
|
50
|
1.70
|
0.01
|
2 minutes / minit
|
10.5
|
|
D
|
60
|
1.40
|
0.05
|
2 minutes
/minit
|
11.2
|
|
E
|
40
|
1.60
|
0.04
|
1 minutes
/minit
|
12.4
|
Table 11.1/ jadual 11.1
(a)
What is meant by power
Apakah maksud kuasa ?
[1 mark] / [1 markah ]
(b) Based
on table 11.1, explain the suitable
characteristics of the student to be in the basket ball team. Choose which
student will be in the basketball team and explain your choice.
Berdasarkan ciri-ciri
dalam jadual 11.1, terangkan bagaimanakah anda
menggunakan ciri -ciri itu untuk memilih pelajar yang dikehendaki. Nyatakan
pelajar yang manakah akhirnya menjadi pilihan
anda dan berikan sebabnya.
[10 marks] / [10 markah ]
(c) When a 100m runner reached the finish line, the
runner stopped suddenly and fell on the ground. Explain the situation using the
appropriate physics concept.
Semasa seorang pelari
100 m sampai ke garisan penamat, ia terus berhenti lalu terjatuh jatuh.
Jelaskan dari sudut konsep fizik yang terlibat.
[4
marks] / [ 4 markah ]
( d ) Two
students were asked to run up the stairs to the top floor of a 10 m building.
Data obtained for the two students are as shown by table 11.2.
Dua orang pelajar
diminta berlari menaiki tangga ke tingkat atas sebuah bangunan yang tinggi
tegaknya ialah 10 m.
Data yang didapati bagi kedua-dua pelajar itu ialah seperti dalam jadual
11.2.
|
|
Mass
Jisim / kg
|
Time
Masa / s
|
|
Student 1
Pelajar 1
|
55.0
|
12.0
|
|
Student 2
Pelajar 2
|
60.0
|
14.0
|
Table 11.2/jadual 11.1
Calculate power of each student and determine which student has the
highest power.
Hitungkan kuasa yang dimiliki oleh setiap pelajar itu dan tentukan
pelajar manakah yang mempunyai kuasa
yang lebih tinggi.
[5
marks]/ [ 5 markah]
Power
is rate of work done
-low mass-more agile
-high height-easy to
shoot goal
-responding time fast –
easy to catch ball
-power high(short time
to move brick)-will not tire easily// more energy
-small time to complete
100m run- can run fast
Choose C: low mass,
tall, respond fast, high power & can run fast
-runner has Inertia
-to continue moving forward
-the legs stop, body continue moving forward
-Unstable and fall
Student 1 : power = mgh/t
= 55 x 10 x 10/
12
=458 W
Student 2: power
= 60 x 10 x 10 / 14
=428 W
Student 1 has higher power