les 16

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

What did we do previous lesson?

This lesson

• About the test
• The fall of a skydiver? 
  
• Upthrust and tension.

Goals

• Describe the fall of a skydiver in terms of  air resistance and falling speed.

• Explain the force of upthrust.

• Give examples of the force of tension.

About the test

00:14

Question 1

• What force makes her fall down?

• What will happen to her speed? Explain.

00:30

Question 2

• What will happen to the air resistance as her speed increases?

• What will this do to her falling speed?

00:41

Question 3

• Air resistance and gravity are balanced. What does this mean for her falling speed?

•  How does the graph in the book call this phase?

01:00

Question 4

• How will pulling out her parachute effect the air resistance?

• What will this do to her speed? Explain. 

01:25

Question 5

• What will slowing down do to the air resistance acting on her?

Exercise

Go to page 19 of the textbook. See the graph at the top of the page.

1) How do you call the phase in the fall of  a skydiver where his falling speed doesn't change.

2) Explain why his falling speed is constant at this phase.

Exercise

Go to page 19 of the textbook. See the graph at the top of the page.

1) How do you call the phase in the fall of  a skydiver where his falling speed doesn't change.

Terminal velocity

2) Explain why his falling speed is constant at this phase. The forces of air resistance and gravity are balanced

Terminal Velocity

§ 1.8 Tension and upthrust

How can boats float on water?

What is the force of 

Tension?

Exercise

Discuss with your neighbour.

 Come up with three examples of the force of tension.

Homework

Textbook §1.8

Yellow block questions

Goals

• Describe the fall of a skydiver in terms of  air resistance and falling speed.

• Explain the force of upthrust.

• Give examples of the force of tension.

Next lesson:

More about tension