forces types of forces effects of forces gravity, mass and weight newton’s laws freefall

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Forces Forces Types of Forces Types of Forces Effects of Forces Effects of Forces Gravity, Mass and Weight Gravity, Mass and Weight Newton’s Laws Newton’s Laws Freefall Freefall

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Page 1: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

ForcesForces

Types of ForcesTypes of Forces

Effects of ForcesEffects of Forces

Gravity, Mass and WeightGravity, Mass and Weight

Newton’s LawsNewton’s Laws

FreefallFreefall

Page 2: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

What is force?What is force?

Common symbol: FCommon symbol: FUnit: Newton, NUnit: Newton, N

Equivalent base units: kg-m-sEquivalent base units: kg-m-s-2-2

Page 3: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

Types of ForcesTypes of Forces

Contact ForceContact Force PushPush PullPull FrictionFriction TensionTension Normal ForceNormal Force Upthrust Upthrust

BouyancyBouyancyLiftLift

DragDragResistanceResistance

ThrustThrustEngineEngine

Non-contact ForceNon-contact Force Gravitational ForceGravitational Force

WeightWeight Electrical ForceElectrical Force Magnetic ForceMagnetic Force

Page 4: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

Types of Forces: Contact ForceTypes of Forces: Contact Force

pullNormal Force

Friction

Tension

Page 5: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

Types of Forces: Contact ForceTypes of Forces: Contact Force

Upthrust

Drag

Page 6: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

Replace it with your original text.

Replace it with your original text.

Replace it with your original text.

Replace it with your original text.

Thrust

Types of Forces: Contact Force

Thrust

Page 7: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

Replace it with your original text.

Replace it with your original text.

Replace it with your original text.

Thrust

Types of Forces: Contact Forces

Lift

Page 8: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

Replace it with your original text.

Replace it with your original text.

Replace it with your original text.

Thrust

Types of Forces: Non-Contact Forces

Weight

Weight

Page 9: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

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Replace it with your original text.

Replace it with your original text.

Types of Forces: Non-Contact Forces

Magnetic ForceElectrical Force

Page 10: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

Mass versus WeightMass versus Weight

MassMassAmount of matter in an Amount of matter in an

objectobjectunit: kilogram, kgunit: kilogram, kgDoes not change with Does not change with

locationlocation

WeightWeightGravitational force on Gravitational force on

the objectthe objectUnit: Newton, NUnit: Newton, NEqual toEqual to

Mass x acceleration Mass x acceleration due to gravitydue to gravity

m x gm x gWhere g = 10 msWhere g = 10 ms-2-2

Changes with locationChanges with locationOn earth, always acting On earth, always acting

downwarddownward

Page 11: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

Weight

Normal force

Weight

Air resistance

Page 12: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

Weight

Normal Force

Drag

Friction

Thrust

Page 13: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

Weight

Upthrust

Drag Thrust

Page 14: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

Effects of ForcesEffects of Forces

Change shapeChange shapeRigid bodiesRigid bodies

Change the state of motionChange the state of motionMove from restMove from restSpeed upSpeed upSlow down Slow down StopStopChange its directionChange its direction

Newton’s LawsNewton’s Laws

Page 15: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

Change of Shape

Page 16: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

extension

Page 17: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

Who is Isaac Newton?Who is Isaac Newton?

“Nature and Nature's laws lay hid in night:God said, Let Newton be! and all was light.”

Page 18: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall
Page 19: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

Newton’s Third Law

For every action there is an equal

and opposite reaction

Law of Action and Reaction

Page 20: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

Action and Reaction Forces

Page 21: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

Action and Reaction Forces

Page 22: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall
Page 23: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

Newton’s First Law

If no unbalanced force acts on a body then the

body is in equilibrium.

Law of Inertia

Page 24: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

What is What is InertiaInertia??

The tendency of a body to resist changes in The tendency of a body to resist changes in its state of motion.its state of motion.

It is measured in terms of mass of a body.It is measured in terms of mass of a body.

Page 25: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

When the forces are balanced

The body does not move,orThe body moves

At a constant speedIn the same direction

Page 26: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

Balanced forces

Page 27: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

Balanced Forces

The book stays still!

Page 28: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

Balanced Forces

The airplane moves forwards at constant speed!

Page 29: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

Balanced Forces

The car moves at constant speed!

Drag

Friction

Thrust

Page 30: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

Your Turn!

Question #1, page 104

Page 31: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall
Page 32: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

Newton’s Second Law

An unbalanced force changes the motion of an object. It speeds upOr slows downOr changes directionOr changes speed and direction

Acceleration change in motion

Equation

a = force

mass

Page 33: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

Unbalanced Forces

The car moves from rest.

The car speeds up.

Page 34: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

Unbalanced Forces

The car slows down to stop.

The car slows down.

Page 35: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

The Physics of Falling

Page 36: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

The Physics of Falling

Freefall Motion where only gravity is acting on the bodyAir resistance is negligibleAs the body falls, its

Speed increasesAcceleration is constantAcceleration = g

Page 37: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

The Physics of Skydiving

Page 38: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

The Physics of Falling with Air Resistance

Air resistance increases with speedTerminal Velocity

The maximum speed of a falling objectWhen upward forces balance downward forces

on the object

Page 39: Forces Types of Forces Effects of Forces Gravity, Mass and Weight Newton’s Laws Freefall

The End