# Year 11 – Dynamics

##### Forces
• using Newton’s Laws of Motion, describe static and dynamic interactions between two or more objects and the changes that result from:
• a contact force
• a force mediated by fields
• explore the concept of net force and equilibrium in one-dimensional and simple two-dimensional contexts using: (ACSPH050)
• vector addition by resolution into components
• solve problems or make quantitative predictions about resultant and component forces by applying the following relationships:
• $F_{AB} = -F_{BA}$
• $F_{AB} = {x} = Fcos{\theta}, F_{y} =Fsin{\theta}$

Resource – Newton’s Third Law – 2 pages

• conduct a practical investigation to explain and predict the motion of objects on included planes(ACSPH098)

Investigation – Friction on Inclined Planes – 3 pages

##### Forces, Acceleration and Energy
• apply Newton’s first two laws of motion to a variety of everyday situations, including both static and dynamic examples, and include the role played by friction ($\vec{f}_{friction} = \mu\vec{F}_{N}$)(ACSPH063)

Resource – Newton’s Laws of Motion – 5 pages

• investigate, describe and analyse the acceleration of a single object subjected to a constant net force and relate the motion of the object to Newton’s Second Law of Motion through the use of: (ACSPH062, ACSPH063)
• qualitative descriptions
• graphs and vectors
• deriving relationships from graphical representations including $\vec{F}_{net} = m \vec{a}$ and relationships of uniformly accelerated motion
• apply the special case of conservation of mechanical energy to the quantitative analysis of motion involving:
•
• work done and change in the kinetic energy of an object undergoing accelerated rectilinear motion in one dimension ($W = F_{\parallel}s = Fscos\theta$)
• changes in gravitational potential energy of an object in a uniform field ($\Delta U = mg\Delta h$)
• conduct investigations over a range of mechanical processes to analyse qualitatively and quantitatively the concept of average power ($P = \frac{\Delta E}{\Delta t} , P = F_{\parallel}v = Fvcos\theta$), including but not limited to:
• uniformly accelerated rectilinear motion
• objects raised against the force of gravity
• work done against air resistance, rolling resistance and friction
##### Momentum, Energy and Simple Systems
• conduct an investigation to describe and analyse one-dimentional (collinear) and two-dimensional interactions of objects in simple closed systems (ACSPH064)
• analyse quantitatively and predict, using the law of conservation of momentum ($\Sigma m \vec{v}_{before} = \Sigma m \vec{v}_{after}$) and, where appropriate, conservation of kinetic energy ($\Sigma m v^{2}_{before} = \Sigma m v^{2}_{after}$), the results of interactions in elastic collisions (ACSPH066)

• investigate the relationship and analyse information obtained from graphical representations of force as a function of time
• evaluate the effects of forces involved in collisions and other interactions and analyse quantitatively the interactions using the concept of impulse ($\Delta\vec{p} = \vec{F}_{net}\Delta t$)
• analyse and compare the momentum and kinetic energy of elastic and inelastic collisions (ACSPH066)

Resource – Elastic vs Inelastic Collisions – 2 pages