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:

algebraic addition

vector addition

solve problems or make quantitative predictions about resultant and component forces by applying the following relationships:

F AB=−F BA $\vec F_\textrm{AB} = -\vec F_\textrm{BA}$

Fx=Fcosθ,Fy=Fsinθ $F_x = F\cos\theta, F_y = F\sin\theta$

conduct a practical investigation to explain and predict the motion of objects on inclined planes

Forces, Acceleration and Energy

Inquiry question:

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 f friction=μF

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

deriving relationships from graphical representations including F net=ma  $\vec F_\textrm{net} = m\vec a$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=Fs=Fscosθ $W = F_{\parallel}s=Fs\cos\theta$

ΔU=mgΔh $\Delta U = mg\Delta h$

conduct investigations over a range of mechanical processes to analyse qualitatively and quantitatively the concept of average power   PEΔt $\displaystyle P = \frac{\Delta E}{\Delta t}$, P=Fv=Fvcosθ $P = F_\parallel v = Fv\cos\theta$including but not limited to:

uniformly accelerated rectilinear motion

work done against air resistance, rolling resistance and friction

Momentum, Energy and Simple Systems

Inquiry question: How is the motion of objects in a simple system dependent on the interaction between the objects

conduct an investigation to describe and analyse one-dimensional (collinear) and two-dimensional interactions of objects in simple closed systems

analyse qualitatively and predict, using the law of conservation of momentum
mv before=mv after $\sum m\vec v_{\textrm{before}} = \sum m\vec v_{\textrm{after}}$and, where appropriate, conservation of kinetic energy
12mv2before=12mv2after $\sum\frac{1}{2}m v_{\textrm{before}}^2 = \sum\frac{1}{2}m v_{\textrm{after}}^2$, the results of interactions in elastic collisions

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   Δp =F netΔt $\Delta\vec p = \vec F_\textrm{net}\Delta t$

analyse and compare the momentum and kinetic energy of elastic and inelastic collisions