4,5,6 Flashcards
What are forces?
Push or pull an object to change its state of motion
What is Newton’s first law?
Law of inertia - body will remain either at rest or in a state of uniform motion unless compelled to change by a force actin upon it
What is inertia?
A body’s reluctance to change it’s state of motion
What is Newton’s second law?
Law of acceleration - magnitude and direction of applied force determines magnitude of acceleration given to a body
What is the time through which the foot makes contact with the ground called?
Footfall
What is the mechanical advantage of a second class lever?
More than 1 - suited to strength
What are the 4 factors that improve stabilty
- Lower centre of mass
- Wider base of support
- Vertical line of gravity
- Larger body mass
What are the units for momentum?
Kgms-1
What is the order of a second class lever and where can it be found in the body?
- Fulcrum, Resistance, Effort (FRE)
- Plantar flexion at ankle
What is the order of a first class lever and where can it be found in the body?
- Resistance, fulcrum, effort (RFE)
- Extension at the elbow
What is newton’s third law?
Law of action/reaction - for every action, there is an equal and opposite reaction
What is the order of a third class lever and where can it be found in the body?
- Fulcrum, effort, resistance (FER)
- All other movements
What is the mechanical advantage of a third class lever?
- Less than 1
- Suited to speed/range of movement
How do you calculate acceleration?
Change in velocity / time
How do you work out impulse?
Force x Time
