Friction of a sliding object

# Friction of a sliding object

 Language: English Friction is an important concept in understanding motion. This lesson allows the student to explore friction between different types of materials. How does an object behave when it lies on a surface? What happens when the surface is inclined? What influence does the material of the surface have on the motion? Key Stage 3 Demonstration, Exercise Friction, Motion Distinguish between high friction and low friction. Understand friction as a force. Know about the influence of mass on friction. Know about the influence of contact area on friction. Discuss the properties of different surfaces. What does high and low friction means? Discuss everyday situations when high friction is useful (tires on cars and bicycles, shoes, gloves) and when low friction is useful (skating, skiing, playground slides). What happens in a slope with high and low friction respectively? Discuss how this can be visualized and explored in Algodoo. Let the students create scenes in Algodoo using the suggestions you came up with together or let them use their own ideas. Help the students make decisions and ask guiding questions. Encourage the students to follow the procedure Create – Predict – Interact – Evaluate. Allow the students to follow-up and share their experiences in class after the simulation.
Steps in Algodoo

# Create a scene

Create several slopes by using the plane tool. Assign different frictions/materials to the slopes. Turn on force and velocity vector visualization. Use a small boxes to investigate friction by letting it slide on the different surfaces.

# Make a prediction

Are there differences in how the box is picking up speed when sliding down the different surfaces? Why?

# Run/Interact

Start the simulation and watch the box slide down the different slopes.

# Evaluate

What happens when the angle of the plane is increased? Decreased? Is it the same for all planes?

# Develop scene

Create several parallel planes using rectangular boxes of different materials.

Add a stopper on each end to prevent the box from falling off the track. Use identical boxes on each track to watch the simultaneous sliding down the planes with different friction properties.

Investigate the influence on contact area on friction by using boxes of different sizes. Make sure the boxes have the same mass.

Investigate the influence of mass on friction by assigning different mass to the boxes.