How Different Types of Surfaces Affect Frictional Force

Name: _________________________ Date: 24/9/08

Form: 2 Anthony

How Different Types of Surfaces Affect Frictional ForceAim:To study the effect of different types of surfaces on the magnitude of frictional force

Problem Statement:What is the effect of different types of surfaces on the magnitude of frictional force?

Hypothesis:

The ____________ the ____________, the ____________ is the ____________ of the ______________________ on the wooden block.Variables:__________: _________________________

__________: _________________________

__________: _________________________Apparatus:

Spring balance, wooden block, concrete floorMaterials:Talcum powder, aluminium sheet, sandpaper, graph paperDiagram:

Procedure:1. The apparatus is set up as shown in the diagram.2. A wooden block is hooked to a spring balance.3. The wooden block is then placed on the surface of the floor.4. The wooden block is pulled along the surface of the floor and the reading on the scale of the spring balance is taken when the block starts to move.5. The experiment is repeated by pulling the wooden block on three other different types of surfaces by using aluminium sheet, talcum powder and sandpaper respectively on the surface of the floor6. All the readings are recorded in the table below.

Table of results:

Type of SurfaceCondition of SurfaceReading on the Spring Balance (N)

1st2nd3rdAverage

Surface of the floor

Aluminium sheet on the surface of the floor

Talcum powder on the surface of the floor

Sandpaper on the surface of the floor

1. The reading on the spring balance is the magnitude of the frictional force.2. The reading on the spring balance just __________ the object starts to move represents the __________ ____________ of frictional force that acts on the object.

3. The ____________ types of surfaces affect the ____________ of the frictional force.

(A bar graph of the magnitude of the frictional force against the types of surface is drawn on the graph paper attached)Discussion:1. Among the different types of surfaces, which one gives the

(a) greatest magnitude of frictional force? ____________________ (b) lowest magnitude of frictional force? ____________________2. What is the condition of the surface that causes the

(a) increase of the frictional force on the wooden block? ____________________ (b) decrease of the frictional force on the wooden block? ____________________3. Arrange in descending order the types of surfaces based on the magnitude of frictional force.

________________________________________________________________________4. Define frictional force operationally.

________________________________________________________________________5. Does the area of the surface in contact influence the magnitude of the frictional force? __________

6. (a) Give one other factor which influences frictional force? ____________________ (b) How does the factor stated in 6(a) influence frictional force?

The ____________ an object, the ____________ the frictional force

7. (a) Frictional force always acts in a direction ____________ to the direction of motion.

(b) Draw on the diagram the direction of the frictional force.

8. Frictional force can be increased by increasing the ____________ of the contact surface.9. (a) What can you infer from the results of the experiment?

_____________________________________________________________________ (b) Suggest one way to decrease frictional force on the surface of the floor.

_____________________________________________________________________10. The surface of the road is ____________ so as to ____________ friction between the road and the tyres of vehicles. This prevents vehicles from skidding especially when it rains.

11. Friction is needed to ____________ ____________ or ____________ a moving vehicle.

Conclusion:______________________________________________________________________________________________________________________________________________________