P2.1.5 Forces and Elasticity P2 Physics Ks4 Additional Science Mr D Powell

Connection Connect your learning to the content of the lesson Share the process by which the learning will actually take place Explore the outcomes of the learning, emphasising why this will be beneficial for the learner Demonstration Use formative feedback – Assessment for Learning Vary the groupings within the classroom for the purpose of learning – individual; pair; group/team; friendship; teacher selected; single sex; mixed sex Offer different ways for the students to demonstrate their understanding Allow the students to “show off” their learning Consolidation Structure active reflection on the lesson content and the process of learning Seek transfer between “subjects” Review the learning from this lesson and preview the learning for the next Promote ways in which the students will remember A “news broadcast” approach to learning Activation Construct problem-solving challenges for the students Use a multi-sensory approach – VAK Promote a language of learning to enable the students to talk about their progress or obstacles to it Learning as an active process, so the students aren’t passive receptors

P2.1.5 Forces and Elasticity A force acting on an object may cause a change in shape of the object. A force applied to an elastic object such as a spring will result in the object stretching and storing elastic potential energy. For an object that is able to recover its original shape, elastic potential energy is stored in the object when work is done on the object to change its shape. The extension of an elastic object is directly proportional to the force applied, provided that the limit of proportionality is not exceeded: F = ke F, is the force in Newtons, N k, is the spring constant in Newtons per metre, N/m e, is the extension in metres, m

a) A force acting on an object may cause a change in shape of the object Task: Think about loading each of these objects with weight and seeing how they extend. We can plot graphs to show the loading and then unloading curves. Draw them in your book. Pair up with another person and discuss why this happens? Write down your findings.

b) A force applied to an elastic object such as a spring will result in the object stretching and storing elastic potential energy. A A spring by it’s nature wants to be coiled. If you apply a force using a weight it works against the structure of the spring The more force applied the more it will extend. If we release the spring the “work” that we have “done” (WD = F x d) is recovered as it is “stored” inside the spring. The sankey diagram shows what occurs when a spring is released. Kinetic Thermal (wasted) EPE Spring

c) For an object that is able to recover its original shape, elastic potential energy is stored in the object when work is done on the object to change its shape. A When you load a wire and stretch in it behaves in a proportional way. If you double the force you also double the extension. This only happens till you get to the “elastic limit” If you go beyond this the wire will permanently deformed Below this the wire acts like a spring and you recover the “Work Done”

Rubber and Polythene....

d) The extension of an elastic object is directly proportional to the force applied, provided that the limit of proportionality is not exceeded: A Spring Extension... Hookes Law We need to think about the form F = k∆L Where the force is related by a constant for the spring.

Example Results for one or two springs (in parallel) Parallel Results Extension (m) Force (N) 0.000 0.005 1 0.017 2 0.035 3 0.050 4 Series Results Extension (m) Force (N) 0.000 0.035 1 0.090 2 0.175 3 0.254 4

P2.1.5 Forces and Elasticity P2.1.5 Forces and Elasticity A force acting on an object may cause a change in shape of the object. A force applied to an elastic object such as a spring will result in the object stretching and storing elastic potential energy. For an object that is able to recover its original shape, elastic potential energy is stored in the object when work is done on the object to change its shape. The extension of an elastic object is directly proportional to the force applied, provided that the limit of proportionality is not exceeded: F = ke F, is the force in Newtons, N k, is the spring constant in Newtons per metre, N/m e, is the extension in metres, m P2.1.5 Forces and Elasticity A force acting on an object may cause a change in shape of the object. A force applied to an elastic object such as a spring will result in the object stretching and storing elastic potential energy. For an object that is able to recover its original shape, elastic potential energy is stored in the object when work is done on the object to change its shape. The extension of an elastic object is directly proportional to the force applied, provided that the limit of proportionality is not exceeded: F = ke F, is the force in Newtons, N k, is the spring constant in Newtons per metre, N/m e, is the extension in metres, m P2.1.5 Forces and Elasticity A force acting on an object may cause a change in shape of the object. A force applied to an elastic object such as a spring will result in the object stretching and storing elastic potential energy. For an object that is able to recover its original shape, elastic potential energy is stored in the object when work is done on the object to change its shape. The extension of an elastic object is directly proportional to the force applied, provided that the limit of proportionality is not exceeded: F = ke F, is the force in Newtons, N k, is the spring constant in Newtons per metre, N/m e, is the extension in metres, m