· Theme: Investigating force and energy.
· Learning Area: Force
· Learning Objective: Analysing friction
By the end of the lesson, pupils should be able to:
· Describe the effects of friction.
· Friction happens when two surfaces are in contacts.
· The amount of frictions depends on the type of surfaces in contact.
· Observing, classifying, making inferences, interpreting data, making conclusions, comparing and contrasting.
Vocabulary/ New Words:
· Friction, force, opposes, movement, opposite, direction, two surfaces, rub against, palms, heat, opposing the motion, wear out, rubbing surfaces, brakes, tyres, engines, rough surface, more friction, smooth surface, ancient.
· Having an interest and curiosity towards the environment.
· Being diligent and persevering.
· Realising that science is a means to understand nature.
· Thinking rationally
- jar, boxes of different weight, shoes, matches.
Point(s) to Note:
- smooth surface has less friction compare top rough surface;
- heavier object experiences higher friction compared to lighter objects.
Teacher plays the Introduction component. Teacher gives the situation to open the lid of jar using dry hands or oily hands. Which is easier? Which situation has more/less friction? View the video of hovercraft moving on rough surface and smooth surface. Which is easier? Which surface has more/less friction?
Test pupils on their common sense these two situations. Accept their answers. Allow pupils to give some other examples of rough surfaces and smooth surfaces. Which types of surfaces has more/less friction?
Teacher plays the video clips concerning friction. Teacher recaps the concept of friction that opposes the movement of an object. Friction occurs when two surfaces rub against each other.
Teacher gives the three examples in our daily life that shows the effects of friction. Ask pupils to rub their palms and feel the heat that produce by friction. From the video clip of pushing car, tell the pupils that friction between its tyres and the floor opposing the motion of the car. Show the video on jogging. Pupils expose to the concept that friction causes wear and tear on the soles of shoes.
Allow pupils to give some other effects of friction. Ask pupils list them down on a piece of paper and present it to the class.
Component: Content 1
Teacher plays the videos on opening jar lid. Ask a volunteer to choose the correct answer. Pause the video for a while, encourage the pupils to give some possible answers. Then, continue with the reason why it is easier to open with the dry hands compare to oily hands. Play the videos on hovercraft move on rough surface and smooth surface. Ask a volunteer to choose the correct answer. Pause the video for a while, encourage the pupils to give some possible answers. Then, continue with the reason why it is easier to move the hovercraft on smooth surface. Play the video of pushing the lighter object and heavy object. Ask a volunteer to choose the correct answer. Pause the video for a while, encourage the pupils to give some possible answers. Then, continue with the reason why it is easier to push the lighter object than the heavy object. Teacher helps pupils to conclude that amount of friction depend on type of the surface in contact and the mass of an object. Ask pupils to give various examples on these conditions.
Component: Content 2
There are seven questions in this activity.
Pupil has fifteen seconds to answer each question. This activity is game based. It covers all learning outcomes.
There are five questions in this component cover the learning outcomes. For Questions 1 to 3, allow pupils choose the correct answers for the objective questions. Q4 contains of drag and drop, pupils need to drag and drop the correct answers for the questions appeared. Q5 consists of true or false questions. Pupils need to identify whether the statements are true or false.
Teacher can use the evaluation that will assess the pupils’ understanding of the lesson.
Teacher plays the Extension component concerning ancient people. Guide pupils to understand that how ancient people use the rubbing of dry stick and dry block of wood to make fire. They also try to overcome friction by using wooden roller to transport heavy load. Ask pupils to give other examples of how ancient people overcome friction.
Teacher concludes the lesson by playing this component to further reinforce understanding of the lesson. Teacher asks pupils to describe the effects of friction. Prompt pupils to list the effects of friction in a class.