Science · Year 5 · Forces in Action · Summer Term

Friction and Surfaces

Testing how different surfaces affect the movement of objects and the heat generated by contact.

• National Curriculum Attainment Targets
• NC-KS2-Science-Y5-Forces-2

About This Topic

Friction acts as a force that resists motion between surfaces in contact, and Year 5 students explore how different textures influence object movement and produce heat through rubbing. They test ramps with surfaces like sandpaper, carpet, and plastic to measure sliding distances or times, linking results to everyday scenarios such as car tyres gripping roads or shoes on wet floors. This work aligns with the National Curriculum's focus on forces, emphasising fair testing and variable control.

Students evaluate friction's dual role: it enables control in walking or braking but slows unwanted motion in machines. Through analysing materials like rubber soles or oily surfaces, they design experiments to quantify friction's effects, fostering skills in prediction, measurement, and evidence-based conclusions. These activities connect physical science to design technology, preparing pupils for topics like mechanisms.

Active learning suits friction perfectly because the force is invisible yet immediately detectable through touch and sight. When students predict outcomes, test surfaces hands-on, and compare group data, they build confidence in scientific method and retain concepts through direct sensory experience.

Key Questions

1. Evaluate whether friction is always a force that we want to reduce.
2. Analyze how different materials help us maintain control while driving or walking.
3. Design an experiment to measure the invisible force of friction between two solids.

Learning Objectives

• Compare the distance an object travels on surfaces with different coefficients of friction.
• Explain how surface texture influences the amount of heat generated by friction.
• Design an experiment to measure the force of friction between two specific materials.
• Evaluate whether friction is always a force that should be reduced in mechanical systems.
• Analyze how different surfaces contribute to grip and control in walking or driving scenarios.

Before You Start

Forces and Magnets

Why: Students should have a basic understanding of forces as pushes or pulls and how they affect motion.

Properties of Materials

Why: Familiarity with different material properties, such as smooth or rough textures, helps students make predictions about friction.

Key Vocabulary

Friction	A force that opposes motion when two surfaces rub against each other. It can cause objects to slow down or stop.
Surface Texture	The roughness or smoothness of a surface. Rougher surfaces generally create more friction than smoother ones.
Coefficient of Friction	A number that represents the ratio between the force of friction and the normal force pressing two surfaces together. It indicates how 'grippy' surfaces are.
Heat Generation	The production of thermal energy as a result of friction between surfaces rubbing together.
Grip	The ability of a surface to hold onto another surface without slipping. Good grip is often due to friction.

Watch Out for These Misconceptions

Common Misconception

Friction is always bad and should be eliminated.

What to Teach Instead

Friction provides grip for walking, braking, and sports. Ramp races let students experience slipping on smooth surfaces versus control on rough ones, prompting them to debate its benefits through shared evidence.

Common Misconception

Smoother surfaces always produce less friction.

What to Teach Instead

Oils and lubricants reduce friction on smooth surfaces too. Hands-on oiling of sliding blocks shows this, and group comparisons help students refine ideas beyond surface texture alone.

Common Misconception

Friction only occurs between solid objects.

What to Teach Instead

It acts between solids, liquids, and gases, like air resistance. Balloon drop tests versus feather drops reveal this, with peer explanations clarifying broader applications.

Active Learning Ideas

Ramp Testing: Surface Showdown

Pupils select objects like toy cars and test them down ramps covered in foil, sandpaper, carpet, and cloth. They measure travel distance or time with rulers and stopwatches, recording in tables. Groups discuss which surface creates most friction and why.

45 min·Small Groups

Heat Friction Hunt

Provide pairs with wooden blocks, sandpaper, and thermometers. Students rub surfaces vigorously for one minute and measure temperature rise. They repeat with smoother materials and graph results to compare heat generation.

30 min·Pairs

Braking Design Challenge

Teams build simple car models from cardboard and straws, testing braking on inclines with added rubber bands or fabric. They modify for best control and present findings to the class.

50 min·Small Groups

Whole Class Friction Vote

Display images of scenarios like skiing or cycling. Class votes on friction's usefulness, then tests mini-models to confirm. Tally results on board for discussion.

20 min·Whole Class

Real-World Connections

• Tire manufacturers design tread patterns to maximize friction between car tires and the road surface, ensuring safe braking and cornering in various weather conditions.
• Shoe designers use different rubber compounds and sole patterns to create grip for athletes, preventing slips on sports courts or trails.
• Engineers consider friction when designing machines, sometimes needing to reduce it with lubricants to prevent wear and overheating, and other times needing to increase it for braking systems.

Assessment Ideas

Exit Ticket

Provide students with a small toy car and three different surfaces (e.g., smooth plastic, carpet square, sandpaper). Ask them to: 1. Predict which surface will cause the car to travel the furthest. 2. Briefly explain their prediction based on surface texture. 3. Record the actual distance traveled on each surface.

Discussion Prompt

Pose the question: 'Is friction always a force we want to reduce?' Ask students to provide at least two examples where friction is helpful and two examples where it is unhelpful, explaining their reasoning for each.

Quick Check

Show images of different scenarios (e.g., an icy road, a person walking on sand, a bicycle brake being applied). Ask students to identify the role of friction in each scenario and whether it is helping or hindering movement, using vocabulary like 'grip' or 'resistance'.

Frequently Asked Questions

How do I teach friction experiments in Year 5?

Start with predictions on ramp surfaces, then conduct fair tests measuring speed or distance. Use toy cars and varied materials like felt or bark. Follow with data tables and bar graphs to analyse patterns, linking to key questions on friction's role in control.

What are common friction misconceptions for KS2?

Pupils often think friction is solely negative or ignores its presence in fluids. Address via demos like tyre treads on wet paper versus dry, encouraging evidence from tests to shift views. Structured talks reinforce that friction aids safety in driving and walking.

How can active learning help teach friction and surfaces?

Active methods make friction tangible: students feel heat from rubbing, predict ramp outcomes, and modify designs for grip. Small group rotations ensure participation, while sharing data builds collaborative skills. This sensory engagement turns abstract forces into memorable, evidence-driven understanding.

How does friction link to everyday life in the curriculum?

Connect to tyres preventing skids, shoe soles for walking, or lubricants in bikes. Pupils analyse these via experiments, evaluating when to reduce or increase friction. This real-world tie strengthens relevance and supports cross-curricular links to design and technology.