Y2_T4_LSN4.1

• Science
• Middelbare school
• havo, vwo
• Leerjaar 2

Topic 4

MOVEMENT IN THE WORLD GRADES:

• LABJOURNAL (4X)
• QUIZ (1X)
• TOOTHPASTE PROJECT (2X)
• TEST (4X)

§4.1 Forces

p. 154-157

ex 1-11 p 158-161

Check out plan in magister!

§4.1 - Learning Goals:

Content

I can explain what a force is.

I can identify different types of forces.

Language

I can explain how different forces work on objects. 

I can explain how they can interact with each other.

Skills

I can calculate the gravitational force acting on an object.

I can draw arrows on a force diagram with the correct point of application, magnitude and direction.

I can calculate the resultant force of forces going in the same direction or opposite directions of each other.  

VWO ONLY - I can calculate the resultant force of two perpendicular forces

P.154-157

§4.1 - Learning Goals:

LG - Step 1: Read the learning goals above carefully. In the 3rd column mark the ones you feel good about with a “+” and the ones you might be a bit worried about with a “-”.

LG - Step 2: Take a good look at the categories of learning goals and compare them to your scores from S1. Now rank your categories from strongest to weakest using the letters A, B & C. (A - being strongest.)

LG - Step 3: Discuss what you have just filled in on your table with your neighbour(s). Try to explain / argue why you made that choice and ask the person for clarifying questions if need be.  

LG - Step 4: Think about what you have just discussed. Make any necessary changes in the marking of your table if need be. Use the last column please!

LG - Step 5: Based on the steps you have just completed, take a look at the table below. What 3 things / goals are you going to focus on this paragraph? Please write them down below.

Share at least on goal.

§4.1 - Wordbank

§4.1 - Wordbank

WB - Step 1: Take a look at the wordbank above, these are the new keywords for §4.1 - Forces. Complete the wordbank by marking a “✓” if you agree with what is said and leave it empty if not. 

WB - Step 2: Discuss what you have just filled in on your table with your neighbour(s). Try to explain / argue why you made that choice and ask the person for clarifying questions if need be.  

WB - Step 3: Take a look at the separate worksheet activity WB-1. Look at the images and text, try to complete them using the words from the wordbank above. You do this together if you want. 

WB - Step 4: Think about what you have just done and discussed. Make any necessary changes in the marking of your table if need be. Please use a different colour.

WB - Step 5: Based on the steps you have just completed, take a look at the table below. What 3 things / goals are you going to focus on in this paragraph? Please write them down below.

A world of Forces:

Forces are all around us

• You can’t see them
• You can only see their effect

The things forces can do:

• Object changes shape
• Object starts to move
• Object changes speed
• Direction of object changes

P.154-157

Types of Forces:

• Gravity 
• Applied force 
• Air resistance 
• Friction 
• Tension force 
• Spring force 
• Normal force 

P.154-157

F​g​​

F​a​​

F​air​​

F​f​​

F​t​​

F​s​​

F​n​​

Magnitude of Forces:

Force is measured in Newtons

• The force needed to lift 1 kg = 9.81 N on earth
• On the moon the force needed is only 1.6 N
• The mass is the same
• Gravitational force is different

P.154-157

Calculation gravitational force:

•        = gravitational force in Newton or weight
• m = mass in kg
• 9.81 is a constant

P.154-157

F​g​​

F​g​​​​​=m⋅9.81

Example: Peter has a mass of 76 kg. What is his gravitational force, ?

F​g​​

Example: The gravitational force of my cat is 34.3N What is her mass?

F​g​​

Drawing Forces:

Forces are represented by an arrow

It has three things:

• point of application - origin of force
• direction
• magnitude (size) - the longer the arrow, the bigger the force

P.154-157

Adding & subtracting forces:

• Two forces in the same direction are added up

• Two forces in opposite direction are subtracted from each other

If forces are equal, there is no motion

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Adding & subtracting forces:

• Resultant force is the sum of the forces
• It is written as 

Forces in the same direction = add

     

Forces in the opposite direction = subtract

          

P.154-157

F​res​​

Perpendicular forces:

• Combine the forces end to end by making a triangle

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Forces worksheet:

• Try the questions by yourself first.
• Then try together
• Then ask for help

P.154-157

Hw for lesson 2:

• Complete the forces worksheet.
• Complete exercises 1-11 of §4.1 pages 158-161
• Read §4.2 pages 162-165
• Study the glossaries of §4.1-§4.2 on Studygo.

P.154-157