Friction: Forces That Slow Us Down

Year 5 Science Understanding Forces in Our World

Entry Task: Friction Hunt

Look around the classroom Find 3 examples where friction helps us Find 3 examples where friction slows things down Share with your partner

Prior Learning Check: Light

Light travels in straight lines - True or False? Name one natural source of light What happens when light hits a mirror? Can light travel through glass?

What is Friction?

A force that acts between surfaces Always works against movement Happens when surfaces rub together Can be helpful or unhelpful

Vocabulary Match

Match the words to definitions: Friction - Force between surfaces Surface - The outside of an object Resistance - Something that slows down movement Grip - How well surfaces stick together

Helpful vs Unhelpful Friction

{"left":"Walking without slipping\nCar brakes stopping safely\nGripping a pencil to write\nRubbing hands together for warmth","right":"Shoes wearing out quickly\nCar tyres getting hot\nBicycle chains needing oil\nMatches creating unwanted heat"}

Types of Friction

Friction Investigation

Test different surfaces with a toy car Try: smooth desk, rough carpet, sandpaper Measure how far the car travels Record your results in a table

Think and Discuss

Why do racing cars have different tyres for wet and dry weather? How do ice skates work so well on ice? What would happen if there was no friction at all?

Reducing Friction

Oil and grease make surfaces slippery Smooth surfaces have less friction Ball bearings help things roll easily Streamlined shapes reduce air friction

Design Challenge

Design shoes for different activities Football boots - need grip on grass Ballet shoes - need to slide smoothly Hiking boots - need grip on rocks Draw and label your designs

Remember This!

Friction is everywhere around us It can help us or slow us down Understanding friction helps us solve problems Engineers use friction knowledge to make life better