Newton's Laws of Motion

Newton's Laws of Motion

• Sir Isaac Newton was an influential English mathematician, physicist, and astronomer
• He made groundbreaking contributions to physics and mathematics

Newton's Laws

• Law of Inertia
• Law of Acceleration
• Law of Interaction

Law of Inertia

• An object at rest stays at rest
• An object in motion stays in motion unless acted upon by an external force
• Friction plus gravity equals external force
• Gravity is valued at 9.8m/s²

Air Resistance

• Air resistance slows down an object moving through air
• The amount of air resistance depends on the speed, size, and shape of the object.

Law of Acceleration

• The acceleration of an object is directly proportional to the net force acting on it
• Acceleration is inversely proportional to its mass
• F = ma (Force = mass x acceleration)

Units of Measure

• Mass is measured in kilograms (kg)
• Acceleration is measured in meters per second squared (m/s²)
• Force is measured in Newtons (N)

Force

• Force is an influence that causes an object to change its velocity

Acceleration

• Acceleration is a change in motion that is equivalent to a change in velocity

Mass

• Mass is the amount of matter that an object possesses

Weight

• Weight is the force due to gravity

Mass

• Mass is the amount of matter that an object possesses

Law of Interaction

• For every action, there is an equal and opposite reaction

Friction

• Friction is a force that opposes the motion of an object when it comes into contact with a surface
• Static friction is the friction that keeps an object at rest and resists the start of motion
• Kinetic friction happens once an object starts moving resisting the motion of an object that's already sliding or rolling

Force Summation

• A force is a push or a pull resulting from the interaction between forces
• Force diagrams can represent these forces
• Forces are considered balanced when they are the same size and act in opposite directions.
• When forces acting on an object are not the same size, it indicates that the forces are unbalanced, potentially leading to changes in the object's motion

Work

• Work is done when a constant force is applied on an object and causes an object to move in the same direction as the force applied (W = F x d)
• Displacement = √dx² + dy²

Power

• Power is the rate of doing work
• It is the amount of work applied to an object per unit of time (P = w/t)

Energy

• Energy is the ability to do work
• It is the transferred by a force moving an object through a distance.
• Work is a method of transferring energy

Forms of Energy

• Thermal (heat)
• Mechanical (motion)
• Electrical (electricity)
• Radiant (light)
• Nuclear (fission, fusion)
• Chemical (stored)
• Sound (motion)

Mechanical Energy

• It is the energy that is possessed by an object due to its motion or due to its position
• M.E = K.E + P.E

Kinetic Energy

• Kinetic energy is a form of mechanical energy that is present in moving objects
• Factors include Mass and Speed

Potential Energy

• Potential energy is energy at rest and is a form of mechanical energy that is possessed by an object at rest
• Factors include Mass and Height from the ground

Law of Conservation of Energy

• Energy cannot be created or destroyed
• Energy can only be transformed from one form to another
• The total amount of energy in a closed system remains constant over time

Sound

• Sound is energy that travels in waves through a medium (Solid, liquid, or gas)
• Sound is created when something vibrates, sending waves through the air or other materials
• Sound is a mechanical wave (longitudinal wave)
• Longitudinal wave motion is back and forth/proportional to the movement of the sound.
  • Compression is compressed
  • Rarefaction is far apart
• Wavelength is the distance between two consecutive points
• The speed of sound refers to how fast sound waves travel through a medium
• Sound travels faster in solids than in liquids and gases because solid particles are more compact

Reflection of Sound

• Sound waves are reflected when they strike a rigid surface or a barrier
• The reflected sound is called an echo
• Needs one medium to bounce off
• Reverberation is a repeated echo/reflection of sound waves

Refraction of Sound

• Sound waves change direction as they pass from one medium to another
• Needs two or more mediums

Light

• Light is a form of electromagnetic wave that allows us to see objects
• It travels in a straight line
• Light can behave as both a wave and a particle (photon)
• It does not need a medium
• It can travel in a vacuum space
• Light moves as a transverse wave
• Light moves up and down & back and forth
• Visible light is the only light that a person can see
• Wavelength and frequency of light are inversely proportional

Refraction

• Refraction is the bending of light when it passes from one medium to another

Dispersion

• Dispersion is when light converts into the 7 colors waterdrops - prism

Kinds of refraction

• Transparent light passes through completely
• Translucent light passes through partially
• Opaque: No light passes through

Reflection

• Reflection is when light bounces off of a surface or barrier

Specular reflection

• Smooth surface
• Travels in one direction

Diffuse reflection

• Rough surface
• Travels in any direction

Scattering of Light

• Scattering happens when light hits tiny particles in the air and spreads in different directions
• Long wavelength - Red

Heat

• Energy transferred due to a temperature difference
• Transfers from hot to cold temperature
• When heat is absorbed by an object, the added energy causes the particles to vibrate
• The sum of potential energy and kinetic energy of all the particles is the internal energy of the object
• Thermal equilibrium occurs when two or more objects in contact no longer transfer heat between them because they have reached the same temperature

Temperature

• Temperature is the measure of the average kinetic energy of the vibrating particles of an object

Unit of Heat Measurement

• Joule (J) is the SI unit of heat and energy
• 1 calorie (cal) = 4.184 joules (J)
• Kilocalorie (kcal) is used in food energy (1 kcal = 1000 cal)
• 1 kcal = 1000 cal = 4184J
• 1000 × 4.184 = 41847

Heat Transfer

• Heat transfer is the process of thermal energy moving from one object or substance

Conduction

• Occurs in solids and fluids, but the effect is more evident in solids
• Heat is transferred through direct contact

Convection

• Refers to the transfer of heat by the movement of fluids

Radiation

• Refers to the transfer of heat by electromagnetic waves
• The form of energy transmitted by radiation is called radiant energy or EM Radiation

Phases of Matter

• Solid
  • Definite shape
  • Definite volume
• Liquid
  • Shape varies depending on the container
  • Definite volume
• Gas
  • Takes on the shape and volume of the container