Download - Force and motion
![Page 1: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/1.jpg)
Motion & Forces
Motion & Forces
![Page 2: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/2.jpg)
Speed & VelocitySpeed & Velocity
• Speed - the rate of change in position over time (distance/time)
• Instantaneous speed
• Average speed
• How is velocity different from speed? Velocity describes both
speed and direction
![Page 3: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/3.jpg)
Change in Velocity
Change in Velocity
What makes an object change velocity?
![Page 4: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/4.jpg)
ForceForce• Push or Pull
• Forces can cause a change in velocity
• Examples:
GravityMagnetismFriction
![Page 5: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/5.jpg)
Balanced ForcesBalanced Forces
Forces that– act on the same object
– are opposite in direction
– are equal in size
![Page 6: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/6.jpg)
Balanced ForcesBalanced Forces Book on table
1. Weight of the book is downward force caused by gravity
2. Table pushes back with an equal and opposite force
Net force is zero
![Page 7: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/7.jpg)
Unbalanced Forces
Unbalanced Forces
Forces that are NOT opposite and equal
What do they cause?
CHANGE IN VELOCITY
ACCELERATION
Forces that are NOT opposite and equal
What do they cause?
CHANGE IN VELOCITY
ACCELERATION
![Page 8: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/8.jpg)
FrictionFrictionForce that opposes motion between 2 surfaces
Depends on the:• types of surfaces•force between the surfaces
Force that opposes motion between 2 surfaces
Depends on the:• types of surfaces•force between the surfaces
![Page 9: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/9.jpg)
Types of FrictionTypes of Friction• Static Friction: (Couch Potato)
– Force between objects at rest
• Sliding Friction: (Ice skating)– Solid surfaces slide over each other
• Rolling Friction: (Rollerblading)– An object rolls over a surface.
• Fluid friction: (Submarine)– An object moves through a fluid
![Page 10: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/10.jpg)
FrictionFrictionFriction is greater...
–between rough surfaces
–when there’s greater force between surfaces (such as more weight)
Friction is greater...
–between rough surfaces
–when there’s greater force between surfaces (such as more weight)
![Page 11: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/11.jpg)
LubricantLubricant
Changes sliding friction into fluid friction
![Page 12: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/12.jpg)
FrictionFriction
Is friction always bad?
![Page 13: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/13.jpg)
GravityGravity
The attractive force between all objects in the universe
![Page 14: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/14.jpg)
Acceleration of Gravity
Acceleration of Gravity
Near the surface of the earth the acceleration due to gravity is 9.8 m/s/s
![Page 15: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/15.jpg)
Newton’s 1st Law
Newton’s 1st Law
An object at rest remains at rest and an object in motion will continue moving at a constant velocity unless acted on by unbalanced forces.
![Page 16: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/16.jpg)
Newton’s Laws of Motion
Newton’s Laws of Motion
![Page 17: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/17.jpg)
Newton’s 1st Law
Newton’s 1st Law
INERTIA
• tendency of an object to resist any change in its motion
• increases as mass increases
![Page 18: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/18.jpg)
Newton‘s 2nd Law
Newton‘s 2nd Law
If more force is applied, an object will be accelerated _____more
![Page 19: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/19.jpg)
Newton’s 2nd Law
Newton’s 2nd Law
• More force means more acceleration
• More mass means less accelerationForce = mass X acceleration
F = ma
![Page 20: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/20.jpg)
Newton’s 3rd Law
Newton’s 3rd Law
For every action, there is an equal and opposite reaction.
Forces occur only in pairs– Act on different objects– Equal and opposite
![Page 21: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/21.jpg)
Newton’s 3rd Law
Newton’s 3rd Law
The hammer exerts a force on the nail to the right.
The nail exerts an equal but opposite force on the hammer to the left.
![Page 22: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/22.jpg)
Momentum
Momentum
![Page 23: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/23.jpg)
Terminal VelocityTerminal Velocity
The final speed of a falling object.
![Page 24: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/24.jpg)
Terminal VelocityTerminal Velocity
Air resistance is offsetting the the weight of the object
![Page 25: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/25.jpg)
![Page 26: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/26.jpg)
ForcesForces
EndEnd
![Page 27: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/27.jpg)
ForceForce
Aristotle's idea:
For an object to move at a constant speed, a constant force must be applied.
![Page 28: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/28.jpg)
ForceForce
Newton’s idea:
An object moving at a constant speed will continue at that speed without additional force being applied.
![Page 29: Force and motion](https://reader033.vdocuments.net/reader033/viewer/2022061116/54664b7daf79594a1f8b50d0/html5/thumbnails/29.jpg)
Balanced ForcesBalanced Forces