Forces

**Inquiry question:** How are forces produced between objects and what effects do forces produce?

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

Explore the concept of net force and equilibrium in one-dimensional and simple two-dimensional contexts using:

algebraic addition

vector addition

vector addition by resolution into components

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

*F**x*=*F*cos*θ*,*F**y*=*F*sin*θ*

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

Forces, Acceleration and Energy

**Inquiry question:** How can the motion of objects be explained and analysed?:

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*⃗ 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

changes in gravitational potential energy of an object in a uniform field Δ*U*=*mg*Δ*h*

conduct investigations over a range of mechanical processes to analyse qualitatively and quantitatively the concept of average power *P*=Δ*E*Δ*t* , *P*=*F*∥*v*=*Fv*cos*θ* 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

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

analyse qualitatively and predict, using the law of conservation of momentum

∑*mv*⃗ before=∑*mv*⃗ after and, where appropriate, conservation of kinetic energy

∑12*mv*2before=∑12*mv*2after , 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 Δ*p*⃗ =*F*⃗ netΔ*t*

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