Lesson 6 — 1.3 Friction

• Natuurkunde / Scheikunde
• Middelbare school
• havo
• Leerjaar 1

This lesson

• The homework
• What is friction?
•  Reducing and increasing friction
• Working on exercises

Learning goals

• Give examples of friction
• Describe the effect of friction on motion
• Explain how to reduce friction
• Describe how friction can be useful

Discussing the homework

Workbook question E

	Thrust of the car (N)	Friction (N)	Air resistance (N)	Resultant force (N)
A	1500	700	800
B	3000	500	100
C	1000	600	500
D	2500	900	400

Workbook question E

	Thrust of the car (N)	Friction (N)	Air resistance (N)	Resultant force (N)
A	1500	700	800	0
B	3000	500	100
C	1000	600	500
D	2500	900	400

Workbook question E

	Thrust of the car (N)	Friction (N)	Air resistance (N)	Resultant force (N)
A	1500	700	800	0
B	3000	500	100	2400
C	1000	600	500
D	2500	900	400

Workbook question E

	Thrust of the car (N)	Friction (N)	Air resistance (N)	Resultant force (N)
A	1500	700	800	0
B	3000	500	100	2600
C	1000	600	500	100
D	2500	900	400

Workbook question E

	Thrust of the car (N)	Friction (N)	Air resistance (N)	Resultant force (N)
A	1500	700	800	0
B	3000	500	100	2400
C	1000	600	500	100
D	2500	900	400	1200

What is friction?

What is friction? — Exercise

In pairs of two, answer the following questions in your notebook:

• Give at least 8 examples of friction.
• Describe the effects of friction.
• What is the cause of friction?

What is friction? — Exercise

Give at least 8 examples of friction.

What is friction? — Exercise

Describe the effects of friction.

Phet

• It slows things down
  

• Works in the opposite direction of a movement
  

• generates heath
  

What is friction? — Exercise

What is the cause of friction?

Friction

• A force between two sufraces moving over each other.
  

• Works in the opposite direction of an objects motion.

• Slows objects down.
  

• Generates heath.

Friction demonstration

Reducing and using friction

Exercise

In pairs of two write down in your note book:

- at least 5 situations where friction is reduced.

- at least 5 situations where friction is useful.

Increasing friction

Reducing friction

Learning goals

• Give examples of friction
• Describe the effect of friction on motion
• Explain how to reduce friction
• Describe how friction can be useful