CH - 8

Question 1

wht is biomechanics?

Answer 1

• sceince of movement of living body
• bones, tendons, muscle, ligament, work together
• produce movement

Question 2

newtons laws of motion

Answer 2

1st law - if a body is in motion remains in motion and if a body is at rest it remains at rest until and unless an external force is acted upon them.
- football, sprint
2nd law - force = mass into acc.
- cricket ball catch move back
- baseball bat
3rd law - every action equal and opposite reaction
- swimming, jumping

Question 3

wht are levers and its types?

Answer 3

lever - bones joints mucles
- rigid bone
- muscle on which force is acted
- turning movement
- fulcrum fixed point
- load kept on rigid structure

types-
1st class lever
2n dclass lever
3rd class lever

Question 4

1st class lever

Answer 4

fulcrum in middle
- eg - throwing ball
fulcrum - elbow
effort - tricep
load - ball
- eg - tilting head
- eg- scissors

Question 5

2nd class lever

Answer 5

load in middle
- eg- standing at toe [heel raise]
fulcrum - ankle joint
effort - gastronemius
load - body
- eg - trolly pushing

Question 6

3rd class lever

Answer 6

• force in middle
  -eg - bicep curl
  fulcrum- elbow joint
  effort - biceps
  load - arm
• eg - eyebrow pluck pin

Question 7

equilibrium

Answer 7

state of balance of all forces acting upan the body
- sum of all acting force is zero
- scienitfic term for - balnce - stability

Question 8

types of equilibrium?

Answer 8

static
dynamic

Question 9

define static/ dynamic equilibrium

Answer 9

static - state of balance
- body at rest
- centre of gravity not in static position
- eg - stand on one leg

dynamic - state of balance
- of all forces acting upon the moving body
- no change in speed or direction occurs
-eg - run, gymnastics

Question 10

centre of gravity?

Answer 10

• imaginary point around which body is balanced
• human centre of weight = cog
• cog chnages direction acc to movement
• for better skilld knowledge of cog is imp

Question 11

friction?

Answer 11

• force acts parllel to movement , resists movement
• works in opp directin of force
• more rough more friction

Question 12

types of friction?

Answer 12

1. static - which exists before object starts to move
2. sliding - when object slides
3. rolling - when object rolls
4. fluid - movement hindered by air or water

Question 13

projectile in sports

Answer 13

• anything thrown/ jumped in air
• follow a certain path of flight - PARABOLA
• balls, javelin
• 45 degree max dist.
• FOOTBALL, HOCKEY, GOLF

Question 14

factors that affect proejctile ?

Answer 14

• angle of projection
• velocity
• projectin
• relative height of projection
• angle of projECTILE

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