Free- body Diagram
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![Page 1: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/1.jpg)
Free-body Diagram
![Page 2: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/2.jpg)
Homework
To a 10.0-kg table, three forces were applied on it.
F1 = 5.00 N, South
F2 = 6.00 N, East
F3 = 4.00 N, West
1. Using the component method, what is the net force applied on the table?
![Page 3: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/3.jpg)
Homework
To a 10.0-kg table, three forces were applied on it.
F1 = 5.00 N, South
F2 = 6.00 N, East
F3 = 4.00 N, West
2. If a fourth force was applied and made the net force zero, what is the magnitude and direction of this fourth force?
![Page 4: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/4.jpg)
Homework
Provide the FBD of the system (in red text) in the following scenarios and identify the agents of all forces cited.
1. a stone in midair after thrown upwards
2. a balloon-powered car moving at a constant speed
3. a balloon-powered car moving with a completely deflated balloon
![Page 5: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/5.jpg)
Homework
• A certain balloon-powered car has a mass of 50.0 grams. The gushing air from its balloon provides a thrust force of 0.30 Newton. If the car is accelerating at 2.00 m/s2 for the first 5.00 meters, do you think friction is acting on the car? Defend your answer by showing your solutions.
![Page 6: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/6.jpg)
Objectives
• Recall the Laws of Motion. • Construct the free-body diagram of the
forces acting on a body. • Determine the magnitude of forces acting
on a body.
![Page 7: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/7.jpg)
Laws of MotionIn memory of the past lesson…
![Page 8: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/8.jpg)
Can you remember?
What are the three laws of motion
proposed by Einstein?
![Page 9: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/9.jpg)
Can you remember?
What are the three laws of motion
proposed by Isaac Newton?
![Page 10: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/10.jpg)
What law has this provision?
For every action, there is an equal but
opposite reaction.
![Page 11: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/11.jpg)
What law has this provision?
Every body continues in its state of rest, or of motion in a straight line
at constant speed, unless it is compelled to change that state by a
net force exerted upon it.
![Page 12: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/12.jpg)
What law has this provision?
The acceleration produced by a net force on a body is directly
proportional to the magnitude of the net force, is in the same direction as the net force, and is inversely proportional to the mass of the
body.
![Page 13: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/13.jpg)
Free-body Diagram
![Page 14: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/14.jpg)
Balloon-powered Cars
ALIN ANG NAIBA?
![Page 15: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/15.jpg)
Balloon-powered Cars
As the air is expelled from the balloon, the car moves. What are the forces acting on it?
![Page 16: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/16.jpg)
Free-body Diagram
A free-body diagram is a physical model that represents all forces acting on a system.
![Page 17: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/17.jpg)
Some Types of Forces
• Weight - the gravitational pull of the earth
• Friction - the contact force that acts to oppose sliding motion between surfaces
• Normal - the contact force exerted by a surface on an object
• Thrust - a general term for the forces that move objects
Read p. 94 of Glencoe for the complete list.
![Page 18: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/18.jpg)
When constructing the FBD,
Always identify the SYSTEM.
![Page 19: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/19.jpg)
Balloon-powered Cars
As the air is expelled from the balloon, the car moves. What are the forces acting on it?
![Page 20: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/20.jpg)
Balloon-powered Cars
As the air is expelled from the balloon, the car moves. What are the forces acting on balloon-powered car?
![Page 21: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/21.jpg)
How would one know that a force should be in the FBD?
For every force there should be
an AGENT.
![Page 22: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/22.jpg)
How would one know that a force should be in the FBD?
If you cannot identify the agent that applies or causes
the force, then that force should not be part of the
FBD.
![Page 23: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/23.jpg)
Balloon-powered Cars
What are the agents applying these forces?
![Page 24: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/24.jpg)
Qualitative FBD
.
![Page 25: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/25.jpg)
Quantitative FBD
• Construct the FBD.
MassesBear = 120 gTable = 12 kg
![Page 26: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/26.jpg)
355 g
125 g
25.0 kg1. Determine the magnitude of the weight (in Newton) of the following:
a. starb. blue pillowc. table
W = 1.23 N
W = 3.48 N
W = 245 N
![Page 27: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/27.jpg)
355 g
125 g
25.0 kg2. Determine the normal force acting on the following:
a. starb. blue pillow c. table
Fn = 1.23 N
Fn = 4.70 N
Fn = 250. N
![Page 28: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/28.jpg)
Simple Drills
F applied = 20.0 N
f = 20.0 N
Describe the direction of the system if it is at rest.
![Page 29: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/29.jpg)
Simple Drills
F applied = 20.0 N
f = 20.0 N
Describe the velocity of the system if it is at rest.
![Page 30: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/30.jpg)
Simple Drills
F applied = 20.0 N
f = 20.0 N
Describe the velocity of the system if it is moving 30 m/s.
![Page 31: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/31.jpg)
Simple Drills
F applied = 20.0 N
Describe the direction of the system if it is moving.
![Page 32: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/32.jpg)
Simple Drills
F applied = 20.0 N
Describe the velocity of the system if it is moving.
![Page 33: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/33.jpg)
Seatwork
• Use a piece of size 4. • Listen to the instructions carefully.
![Page 34: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/34.jpg)
Number 1
f = 15.0 N
Describe the motion of this body moving to the right. (speeding up, slowing down, constant velocity)
![Page 35: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/35.jpg)
Number 2
f = 15.0 N
Describe the motion of this body moving to the right. (speeding up, slowing down, constant velocity)
F applied = 20.0 N
![Page 36: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/36.jpg)
Number 3
f = 15.0 N
What is the net force acting on the body (magnitude and direction)?
F applied = 20.0 N
![Page 37: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/37.jpg)
Number 4
f = 15.0 N
If the body has a mass of 5.00 kg, what is its acceleration (magnitude and direction)?
F applied = 20.0 N
![Page 38: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/38.jpg)
Number 5
f = 15.0 N
How many seconds will it take for this body to increase its speed by 5.00 m/s?
F applied = 15.0 N
![Page 39: Free- body Diagram](https://reader034.fdocuments.in/reader034/viewer/2022051114/56812bd4550346895d90379e/html5/thumbnails/39.jpg)
End of Session