E N D
SAINS SUKANBIOMEKANIK BADMINTON ONG KONG SWEE ongkongswee@gmail.com 0168626509
Kinesiologi Biomekanik PJ Suaian Fisiologi Senam Lakuan Motor Athletic training Sejarah Sukan Pedagogi Falsafah Sukan Seni Sukan Psikologi Sukan Istilah Bidang
Istilah Bidang Sains Sukan Biomekanik Fisioterapi Fisiologi Senam Lakuan Motor Athletic training Pemakanan Pedagogi Pengurusan Sukan Sosiologi Psikologi Sukan
KINESIOLOGI • Kajian pergerakan manusia SAINS SUKAN • Kajian sistematik membabitkan sains dalam sukan BIOMEKANIK • Sintesis bidang biologi dan mekanik untuk memahami dan menjelaskan pergerakan
BIOMEKANIK Bio – benda hidup atau sistem biologi Mekanik – analisis daya dan kesannya “Analisis kesan daya dalam kajian aspek anatomi dan fungsi sistem benda hidup” “Aplikasi prinsip-prinsip mekanik dalam kajian benda hidup”
Matlamat • Meningkatkan prestasi • Teknik perlakuan • Peralatan : Apakah perubahan yang boleh dilakukan pada peralatan sukan untuk meningkatkan prestasi ? • Kenapa satu teknik lebih baik daripada teknik yang lain? • Kenapa bentuk badan seseorang lebih baik daripada yang lain? • Pencegahan kecederaan dan pemulihan
Sub-cabang biomekanik MEKANIK Statik Dinamik Kinetik sistem pegun Sistem velositi konstan Kinematik Kinetik
statik: kajian sistem pergerakan konstan • dinamik: kajian sistem pergerakan yang mempunyai pecutan • kinematik: kajian bentuk perlakuan atau deskripsi sesuatu pergerakan • kinetik: kajian tindakan daya
Keupayaan mekanikal • Keupayaan mekanikal jasad adalah hasil daripada pergerakan sendi. • Sistem tuas rangka adalah sistem yang mempengaruhi keupayaan mekanikal jasad. • Tuas jasad manusia terdiri daripada: • Tulang – palang • Sendi – fulkrum • Penguncupan otot – daya • Beban - rintangan
F R Kelas pertama R F Kelas kedua F R Kelas ketiga Sistem Tuas • Tuas dikelaskan kepada kelas pertama, kedua dan ketiga Tuas ditentukan mengikut kedudukan daya, beban, dan fulkrum
Keupayaan mekanikal berkait dengan konsep momen daya (torque) dan equilibrium • Momen daya – kesan daya putaran pada sendi • Momen daya – hasil darab daya dengan lengan momen daya
SISTEM TUAS • sistem tuas membantu dalam keberkesan sesuatu pergerakan. • ST ialah satu struktur yang teguh yang diengselkan (fulkrum) di satu titik dan daya dikenakan kepada kedua-dua hujung struktur tersebut (daya motif dan daya rintangan. daya rintangan daya motif/beban fulkrum
ingat komponen utama ST terdiri daripada satu tuas yang teguh, satu aksis(fulkurum), satu daya motif dan satu daya rintangan. • sistem otot rangka juga bertindak sebagai sistem tuas • terdapat tiga jenis sistem tuas dalam badan kita • Tuas kelas Satu • Tuas kelas Dua • Tuas kelas Tiga
Tuas Kelas Satu • Daya di satu hujung • Baban di satu hujung • Fulkrum ditengah • (contoh) gunting • (contoh) kepala bergerak atas dan bawah
Tuas Kelas Kedua • Daya disatu hujung • Fulkrum disatu hujung • Beban ditengah • (Contoh) wheelbarrel • (Contoh) berdiri dihujung kaki
Tuas Kelas Ketiga • Beban di astu hujung • Fulkrum di satu hujung • Daya di tengah • (contoh) using a tweezers • (contoh) mengangkat barang dengan lengan
Definisi daya • Tolakan atau tarikan • Dicirikan dalam bentuk: • Magnitud • Arah • Titik aplikasi • Garis tindakan • F = ma • Unit : N
Daya raket Bola dipukul oleh raket Rintangan udara berat Arah pergerakan bergantung kepada daya hasilan akhir daripada semua daya yang bertindak
Kuantiti kinematik linear • kajian bentuk perlakuan atau deskripsi sesuatu pergerakan berasaskan masa • Linear • Angular/bersudut
Jenis pergerakan/Motion • Linear Motion • Following a path along line that may be straight or curved. • All parts of a body move the same distance, direction and time. • Eg. Moving from the back from a straight smash to play a straight block.
Jenis pergerakan/Motion • Angular Motion/Rotation • Movement in a curves path or circular. • When a body on a circular path about a central line or point. • All parts of body move same angle, direction and time. • Example : Smashing action, motion of the racquet.
Hukum Newton • Pertama- Inersia: jasad akan terus pegun atau bergerak dalam garis lurus kecuali suatu daya bertindak ke atas jasad tersebut • Kedua – Pecutan: Pecutan sesuatu jasad adalah berkadar terus dan pada arah tindakan daya serta berkadar songsang dengan jisim • a= F/m • Ketiga- Aksi Reaksi : Bagi setiap aksi wujud reaksi yang sama dan bertentangan arah
An object will continue in a state of rest or uniform motion unless acted upon by an external force. If an unbalanced force acts on an object, it will accelerate in the direction of the unbalanced force. If an object is given a certain initial velocity and there are no unbalanced forces acting on it, the object will continue along its original path in a straight line. Newton’s First Law
When a force acts on an object, the object is accelerated by an amount directly proportional to the force applied and inversely proportional to the mass of the object (F = ma). The greater the force being exerted on an object, the faster the object moves. The greater the mass of the object, the slower the object will move in relation to a lighter object with the same force applied. A big mass (tennis ball) is harder to accelerate than a smaller mass (table tennis ball). Newton’s Second Law
Newton’s Second Law - Hockey • If a player strikes the ball, its acceleration is determined by the mass of the ball and how hard the player hits it (F = ma). • If the ball were heavier (larger mass), it would accelerate less. • If the player hits the ball harder (larger force), the ball accelerates more quickly.
A batter gets an advantage if he uses Newton’s Second Law before stepping onto the plate. Newton’s Second Law • A baseball player on deck getting ready to bat adds weights to their bat to practise swinging, and to warm up their muscles. • If the total mass of the weights added is equal to the initial mass of the bat, then the weight is doubled. • If the batter swings at a constant speed (a), and applies a uniform force throughout (F), we can apply Newton’s Second Law. • When he removes the weights, the mass is cut in half, and the acceleration will be twice as fast as before.
Note: A bat has a mass of 2 kg. Newton’s Second Law Q1. A batter swings with 200N of force on deck circle, with weights attached making the bat twice as heavy as usual. What is the bat’s acceleration: a) on the on deck circle? b) at the plate when the weights have been removed? Q2. A bat has an acceleration of 80m/s2. What force was applied to the bat? Q3. A batter at the plate swings with a force of 100N. What is the bat’s acceleration? How does this compare to the answer to Q1.b?
Newton’s Second Law A1.a) F = ma b) F = ma a = F/m a = F/m a = 200N/4kg a = 200N/2kg a = 50m/s2 a = 100m/s2 A2. F = ma F = 2kg x 80m/s2 F = 160N A3. F = ma The force applied is a = F/m half that in Q1.b, a = 100N/2kg therefore, the a = 50m/s2 acceleration is halved.
For every action there is an equal and opposite reaction For every force between two objects there is always an equal but oppositely directed force. The normal reaction force is the support force exerted upon an object which is in contact with another stable object. Newton’s Third Law Question: When hitting a baseball, if we call the force on the bat against the ball the action force, what is the reaction force? Normal reaction force Weight
When a swimmer turns, the pool wall pushes against the swimmer with the same force as the swimmer pushes against the pool wall. When a weightlifter pushes against the ground, the ground pushes against the weightlifter with the same force. When a tennis player hits a ball with their racquet, the tennis ball exerts an equal but opposite force on the player’s racquet. Can you think of any more examples? Newton’s Third Law Answer: The reaction force is the force exerted by the ball on the bat.
Newton’s Third Law • For every force exerted by an object, an equal and opposite force is exerted onthe object. • When two hockey players collide, they are both hit with an equal force, even if one is moving and the other is standing still! • Even though a player may be standing still, he still exerts just as much force on the hitting player as the player is delivering to him.
Terima Kasih • Ada soalan ?