SPH3U 2018 FULL Review - Notes PDF

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Catherine Huang’s

SPH3U Full Review 2018-2019

Unit 1: Kinematics 1 Unit 2: Forces Unit 3: Energy and Society 8 Unit 4: Waves and Sound 10 Unit 5: Electricity and Magnetism 18

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Unit 1: Kinematics Chapter 1: Motion in a Straight Line 1.1: Distance, Position and Displacement Kinematics: the study of motion Motion: the change in an object’s location as measured by a particular observer Distance (d): the total length of the path travelled by an object in motion Direction: the line an object moves along from a particular starting point Scalar: a quantity that only has a magnitude (size) Vector: a quantity that has a magnitude (size) and direction Position (⟶d): the distance and direction of an object from a reference point Displacement (Δ⟶d): the change in position of an object ● An arrow is placed above a variable to indicate that it is a vector quantity ● Vector quantities have directions with their magnitudes (ex. 500 m [E]) ● Displacement is read as delta position, meaning the change in position

1.2: Speed and Velocity Average speed (Vav): the total distance travelled divided by the total time taken to travel that distance Average velocity (⟶Vav): the total displacement, or change in position, divided by the total time for that displacement Position-time graph: a graph describing the motion of an object, with position on the vertical axis and time on the horizontal axis Motion with uniform or constant velocity: motion of an object at a constant speed in a straight line Motion with non-uniform velocity (accelerated motion): motion in which the object’s speed changes or the object does not travel in a straight line ● Average speed can be calculated as the change in distance over the change in time ● Average speed is not uniform, and can be in any movement in any direction ● Average velocity can be calculated as the total displacement over the

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change in time ● A position-time graph describes motion over time, where the slope of the graph represents the average velocity over that graph ● Motion with uniform motion/constant velocity is motion at a constant speed in a straight line ● Motion that is at a constant speed but not in a straight line is not uniform

1.3: Acceleration Acceleration (⟶aav): how quickly an object’s velocity changes over time (rate of change of velocity) Velocity-time graph: a graph describing the motion of an object, with velocity on the vertical axis and time on the horizontal axis Motion with uniform acceleration: motion in which velocity changes at a constant rate Instantaneous velocity (⟶vinst): the velocity of an object at a specific instant in time ● Acceleration describes how quickly an object’s velocity changes over time or the rate of change of velocity ● A velocity-time graph shows the acceleration as the slope ● Motion with uniform acceleration, the velocity of an object changes at a constant (uniform) rate ● For motion with non-uniform velocity, average and instantaneous velocities are not necessarily equal

1.4: Comparing Graphs of Linear Motion Acceleration-time graph: a graph describing motion of an object, with acceleration on the vertical axis and time on the horizontal axis ● The area under an acceleration-time graph represents the change in velocity of an object

1.5: Five Key Equations for Motion with Uniform Acceleration ● The five key equations of accelerated motion only apply to motion with uniform acceleration

1.6: Acceleration Near Earth’s Surface Acceleration due to gravity (g): the acceleration that occurs when an

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object is allowed to fall freely; close to Earth’s surface; g has a value of 9.8 m/s2 Free fall: the acceleration due to gravity of an object in the absence of air resistance Terminal velocity: the velocity of an object when the force due to air resistance equals the force due to gravity on the object ● Different places on Earth have different values for g, where places with higher elevation has a lower value for g because they’re further from Earth’s centre ● Objects that move freely in the vertical direction experience acceleration due to gravity (g) ● When the air resistance on something falling is equal to the force due to gravity acting on the object, the object will stop accelerating and experience a constant velocity, called terminal velocity

Chapter 2: Motion in Two Dimensions 2.1: Motion in Two Dimensions- A Scale Diagram Approach Resultant vector: a vector that results from adding two or more given vectors ● Objects move in two dimensions, such as in a horizontal plane and a vertical plane ● To determine total displacement, displacement vectors can be added together using a scale diagram ● Join vectors tip to tail and draw the resultant vector

2.2: Motion in Two Dimensions- An Algebraic Approach Component vectors: vectors which, when added together, give the original vector from which they were derived; one component is parallel to the x-axis and the other is parallel to the y-axis ● Perpendicular vectors can be added algebraically using the Pythagorean theorem and the tangent function ● By using the component method of vector addition, all vector addition problems can be converted into a problem involving two perpendicular vectors

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2.3: Projectile Motion Projectile: an object that moves along a two-dimensional curved trajectory in response to gravity Projectile motion: the motion of a projectile under gravity Time of flight: the time taken for a projectile to complete its motion ● Projectile motion consists of independent horizontal and vertical motions ● The horizontal and vertical motions of a projectile take the same amount of time ● Projectiles move horizontally at a constant velocity ● Projectiles undergo uniform acceleration in the vertical direction due to gravity ● Projectile motion can begin and end at the same or different heights

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Unit 2: Forces Chapter 3: Newton’s Laws of Motion 3.1: Types of Forces Dynamics: the study of the causes of motion Newton (N): the SI unit of force (1 N = 1 kg ⋅ m/s2) System diagram: a simple sketch of all objects involved in a situation Free-body diagram: a simple drawing of an object showing all the forces that are acting on it Applied force (⟶Fa): a force that results when one object makes contact with another and pushes or pulls on it Tension (⟶FT): a pulling force from a rope or string on an object that always points toward the rope or string Normal force (⟶FN): a perpendicular force exerted by a surface on an object in contact with the surface; the normal force always points away from the surface Friction (⟶Ff): opposes the sliding of two surfaces across one another; friction acts opposite to the motion or attempted motion Force of gravity (⟶Fg): force of attraction between any two objects Net force (⟶Fnet): the sum of all forces acting on an object ● Dynamics explains why objects move the way they do ● Forces cause objects to start moving, speed up, slow down, or remain stationary ● A system diagram is a diagram showing all the forces acting upon all the objects in a system ● A free body diagram shows all the forces acting on a singular object ● An applied force results when one object is in contact with another object and either pushes or pulls on it ● Tension is a pulling force exerted on an object by a rope or a string ● Tension only results from a pull ● The normal force always acts perpendicular to the surface it’s on ● Friction is a force that resists the motion or attempted motion of an object ● Friction is always parallel to the surface and acts opposite to motion ● These are all contact forces (require contact between acting objects) ● An example of a non-contact force is gravity

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3.2: Newton’s First Law of Motion Inertia: the property of matter that causes it to resist changes in motion; inertia is directly proportional to the mass of the object First law of motion: an object will remain at rest or continue to move at constant velocity when the net force on the object is zero ● Objects in motion remain in motion, objects at rest remain at rest ● An object moving at constant velocity requires a force of friction to stop it ● If you put a stuffed animal on the dashboard in a car, and the car starts moving abruptly, the stuffy will fall into your lap because it resists the motion of the car ● The car is moving forward and the stuffy is stationary, so it’s more like the dashboard is being pulled out from under the stuffy ● Inertia only resists changes in motion ● A non-zero net force will change the velocity of an object ● A net force is not required to maintain the velocity of an object ● External forces are required to change the motion of an object but internal forces have no effect on the motion of an object

3.3: Newton’s Second Law of Motion Second law of motion: an object will accelerate in the direction of the net force; the magnitude of the acceleration is directly proportional to the magnitude of the net force and inversely proportional to the object’s mass ● The slope of the graph of net force versus acceleration is the mass of the object ● The acceleration of an object is directly proportional to the net force and inversely proportional to the mass

3.4: Newton’s Third Law of Motion Third law of motion: each action force has a reaction force that is equal in magnitude and opposite in direction ● When you exert a force on something, that something will exert an equal in magnitude but opposite in direction force against you ● Action and reaction forces always act on different objects, or different parts of a single object ● When two objects are involved, the two forces are not added together 6

and each object can accelerate 3.5: Using Newton’s Laws ● Tension is a pulling force exerted by a device such as a rope or a string ● If two masses are tied together, the force of tension exerted right on the left block is equal and opposite in direction to the force of tension exerted left on the right block

Chapter 4: Applications of Forces 4.1: Gravitational Force Near Earth Free fall: the motion of a falling object where the only force acting on the object is gravity Terminal speed: the maximum constant speed of a falling object Force field: a region of space surrounding an object that can exert a force on other objects that are placed within that region and are able to interact with that force Gravitational field strength: the force per unit mass acting on an object when placed in a gravitational field ● When an object is falling under the influence of gravity only, the object is said to be in free fall ● Gravity is a non-contact force that pulls on objects due to a gravitational force field ● To determine the force of gravity at a particular location on earth, you use gravitational field strength ● This is the force, per kilogram of mass, acting on an object within a gravitational field ● At Earth’s surface, the gravitational field strength is 9.8 N/kg [down] ● The force of gravity decreases as you get further from Earth’s surface ● Mass is the quantity of matter in an object ● Weight is a measure of the force of gravity acting on an object ● Weight is a vector

4.2: Friction Static friction (⟶Fs): a force of friction that prevents the sliding of two surfaces relative to one another

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Kinetic friction (⟶Fk): the force exerted on a moving object by a surface opposite to the direction of motion of the object Coefficient of friction (μ): the ratio of the force of friction to the normal force Coefficient of static friction (μs): the ratio of the maximum force of static friction to the normal force Coefficient of kinetic friction (μk): the ratio of kinetic friction to the normal force ● When you try to push a chair on the floor, initially it takes additional effort to get it moving than it does to keep it moving ● This is due to static friction, which will keep a stationary object stationary until a great enough force is applied to move it ● Once the object is moving, as the applied force continues to increase, the object begins to accelerate ● If the applied force decreases and the object starts moving at a constant velocity, the applied force must be equal in magnitude to the kinetic friction ● Kinetic friction acts in the opposite direction to the motion of the object ● The magnitude of static friction is greater than or equal to the magnitude of kinetic friction ● The coefficient of friction between an object and a surface depends only on the type of materials

4.3: Solving Friction Problems ● Static friction exists between an object and a surface when the object is not sliding on the surface ● Static friction can be used to move objects ● Kinetic friction always acts in a direction that is opposite to the motion of the object

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Unit 3: Energy and Society Chapter 5: Work, Energy, Power and Society 5.1: Work Mechanical work (W): applying a force on an object that displaces the object in the direction of the force or a component of the force ● Work is a scalar quantity (there is no associated direction) ● Work is measured in joules (N⋅m) ● When a force is applied to an object and the object does not move, no displacement occurs ● When you stand on the floor, your body applies a force equal to your weight, but the floor is not displaced, so your body does not do work on the floor ● An object can experience many forces at a time, so there can positive and negative forces acting upon it ● If you lift an object, you apply positive force upward on it, but the force of gravity applies a force downward on it ● The total work is the algebraic sum of all forces applied ● The work done by a force on an object may be represented graphically by plotting the magnitude of the force, F, on the y-axis and the magnitude of the object’s position, d, on the x-axis ● The area under the graph represents the amount of work done to displace the object ● When a force varies in magnitude during a displacement, the work done is equal to the product of the average force, Fav, and the displacement, Δd 5.2: Energy Energy: the capacity to do work Kinetic energy (Ek): energy possessed by moving objects Work-energy principle: the net amount of mechanical work done on an object equals the object’s change in kinetic energy Potential energy: a form of energy an object possesses because of its position in relation to forces in its environment Gravitational potential energy: energy possessed by an object due to its position relative to the surface of Earth Reference level: a designated level to which objects may fall; considered to

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have a gravitational potential energy value of 0 J Mechanical energy: the sum of kinetic energy and gravitational potential energy ● A moving object has the ability to do work because it can apply a force to another object and displace it ● The energy possessed by moving objects is called kinetic energy ● Kinetic energy is a scalar quantity: it has a magnitude but no direction kg ⋅m❑2 ● EK has the units 2 s❑ ● The total change in energy is equal to the net force ● Potential energy can be considered a stored form of energy ● Once something with gravitational potential energy is dropped from suspension, the energy becomes kinetic energy ● The sum of an object’s kinetic energy and gravitational potential energy is called mechanical energy

5.3: Types of Energy and the Law of Conservation of Energy Thermal energy: the total quantity of kinetic and potential energy possessed by the atoms or molecules of a substance Nuclear energy: potential energy of protons and neutrons in atomic nuclei Energy transformation: the change of one type of energy into another Law of conservation of energy: energy is neither created nor destroyed; when energy is transformed from one form into another, no energy is lost ● The conversion of energy is called an energy transformation ● In an energy transformation, the total amount of energy does not change

5.4: Efficiency, Energy Sources, and Energy Conservation Efficiency: the amount of useful energy produced in an energy transformation expressed as a percentage of the total amount of energy used ● Efficiency is the ratio of the amount of useful energy produced (energy output, or Eout) to the amount of energy used (energy input, or Ein), expressed as a percentage

5.5: Power Power (P): the rate of transforming energy or doing work 10

● Power describes the rate at which energy is transformed, or the rate at which work is done ● Power is a scalar quantity ● Electrical devices transform electrical energy into other forms of energy, and the power rating of these devices can be determined using the equations for power

Unit 4: Waves and Sound Chapter 8: Vibrations and Waves 8.1: What is a Vibration? Vibration: the cyclical motion of an object about an equilibrium point Mechanical wave: the transfer of energy through a material due to vibration Medium: the material that permits the transmission of energy through vibrations Net motion: the displacement of a particle over a certain time interval; the difference between the particle’s initial and final positions Elastic: the property of a medium that returns to its original shape after being disturbed Translational molecular motion: the straight-line motion of a molecule; this motion is typical of gases because the particles in liquids and solids are not free to move in this manner ● If you beat a drum, the vibrations created by the disturbance are transferred throughout the material ● This transfer of energy through a material by particle vibration is called a mechanical wave ● The material it travels through is called a medium ● (can be solid, liquid or gas) ● When vibrating, the medium tends to gain or lose very little energy ● A vibration can travel through a medium because each molecule is connected to neighbouring molecules through intermolecular forces ● These allow the distances between atoms to increase without losing energy ● This makes mechanical waves one of the most efficient forms of energy transfer

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● Net motion is the displacement of a particle over a certain time interval ● After a wave has passed through a medium, particles return to their original location ● Ideally there is not net motion when the particles stop vibrating so their net displacement is zero ● No work is done on them by the wave- no energy is lost by the wave so it can continue indefinitely ● Solids only vibrate slightly ● If they return to their original form after a disturbance, they are elastic ● Rigid materials transfer mechanical waves more efficiently than non-rigid ones ● Mechanical waves in rigid materials last longer, go farther, and go faster than they do in non-rigid mediums ● A less rigid material disperses more energy through absorption, so a vibration weakens quickly ● Liquids are very effective transmitters of sound ● Molecules in a gas are much farther apart than those in a solid or liquid ● Gases rely on translational molecular motion to transfer vibrations ● Gases are less effective than solids and liquids at transmitting vibrations

8.2: Types of Mechanical Waves Transverse wave: a wave in which particles vibrate perpendicular to the direction of the flow of energy (ex. A swing hanging from a tree) Longitudinal wave: a wave in which particles vibrate parallel to the direction of the flow of energy (ex. Pushing a wave through a slinky) Compression: the region in a longitudinal wave in which the medium’s particles are closer together Rarefaction: the region in a longitudinal wave in which the medium’s particles are farther apart Sound: a form of energy produced by rapidly vibrating objects detectable by sensory organs such as the ear ● A transverse wave is a wave in which the vibration occurs perpendicular to the direction of the flow of energy ● When you strum a guitar, you strum from a string attached at two ends, where the stimulus occurs close to one end

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● The vibration moves along the string and reflects off of one end, and moves and reflects of...