Welcome to Physical Science!
This course is a combination of basic physics, the study of energy, and chemistry, the study of matter.
If you click the button below, you can access all of the objectives and standards for our course.
This is a useful tool in studying for tests and the final exam!
This is a useful tool in studying for tests and the final exam!
The Physics of Physical Science
Test #1 Material:
PSc.1.1.1 Explain motion in terms of frame of reference, distance, and displacement.
What is motion? How do we even know that an object has moved?
To know that an object has moved, we first need to establish a FRAME OF REFERENCE. In other words, we need something that we can compare the "moving" object to in order to know that the object has moved. Sometimes your frame of reference could be a tree, or maybe an object on the side of the road. The important thing is that your frame of reference must be stationary (it must not move!). If I am walking down a street, you can compare my position at this moment to something nearby like a tree. If you look at me again after a few seconds and I am a greater distance or lesser distance from the tree, then you know that I have moved.
What is the difference between distance and displacement?
So, you know that I have moved, because you used the tree as a frame of reference. You can easily measure the distance between me and the tree. That's like measuring the distance between two points using a straight line. DISTANCE is a SCALAR measurement--in other words, it's only showing the magnitude of all of my steps. However, DISPLACEMENT is a VECTOR measurement. Displacement refers to exactly how much I have been "displaced" or moved from my starting position. Displacement not only includes the magnitude of the measurement, but also the direction. Therefore, I might have walked on a trail for 100 meters to get to point B (distance), but Point B might just be 40 meters west of my starting position (displacement). Look at the picture below:
To know that an object has moved, we first need to establish a FRAME OF REFERENCE. In other words, we need something that we can compare the "moving" object to in order to know that the object has moved. Sometimes your frame of reference could be a tree, or maybe an object on the side of the road. The important thing is that your frame of reference must be stationary (it must not move!). If I am walking down a street, you can compare my position at this moment to something nearby like a tree. If you look at me again after a few seconds and I am a greater distance or lesser distance from the tree, then you know that I have moved.
What is the difference between distance and displacement?
So, you know that I have moved, because you used the tree as a frame of reference. You can easily measure the distance between me and the tree. That's like measuring the distance between two points using a straight line. DISTANCE is a SCALAR measurement--in other words, it's only showing the magnitude of all of my steps. However, DISPLACEMENT is a VECTOR measurement. Displacement refers to exactly how much I have been "displaced" or moved from my starting position. Displacement not only includes the magnitude of the measurement, but also the direction. Therefore, I might have walked on a trail for 100 meters to get to point B (distance), but Point B might just be 40 meters west of my starting position (displacement). Look at the picture below:
PSc. 1.1.2 Compare speed, velocity, acceleration, and momentum using investigations, graphing, scalar quantities, and vector quantities.
Watch the video below to review the concepts of SPEED, VELOCITY, and ACCELERATION.
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Like distance and displacement, speed and velocity are similar to one another in a scalar-vector relationship.
Speed is a scalar value of simply how fast an object is going. It can be calculated by dividing the change in position by the change in time. Velocity is a vector because it not only explains how fast an object is moving, but also in what direction. *Speed and Velocity are measured in the same units (usually m/s) but velocity could be m/s North, South, East, or West. *Speed cannot be negative, because the smallest change in motion that can exist is 0. *However, velocity CAN be negative. It just means the object is moving backwards (or changed direction). *If speed or velocity is 0, the object is not moving. Acceleration is another vector value, because it demonstrates the rate of change of velocity, or how fast the velocity is changing. *Acceleration is measured in m/s2 or m/s/s (meters per second squared, or meters per second per second). *If acceleration is positive, the object is speeding up. If acceleration is negative, the object is slowing down. If acceleration is zero, the object is moving at a CONSTANT VELOCITY (like cruise control). |
Need more help? Take these tutorials from Khan Academy:
Momentum is a characteristic of all moving objects that depends on the MASS of the object and its VELOCITY.
*Momentum can be calculated using the equation p=mv (momentum = mass x velocity).
*Two objects moving at the same velocity will have different momentum values--the object with more mass will have more momentum than the object with less mass. For example, an 18-wheeler and a car travelling at the same velocity with have different momentum values. The 18-wheeler will have much more momentum, because it has a much greater mass, as opposed to the car, which will have less momentum because of a smaller mass.
*Momentum can be calculated using the equation p=mv (momentum = mass x velocity).
*Two objects moving at the same velocity will have different momentum values--the object with more mass will have more momentum than the object with less mass. For example, an 18-wheeler and a car travelling at the same velocity with have different momentum values. The 18-wheeler will have much more momentum, because it has a much greater mass, as opposed to the car, which will have less momentum because of a smaller mass.
PSc.1.2.1 Explain how gravitational force affects the weight of an object and the velocity of an object in free fall.
Gravity is the force that pulls objects toward one another. Because the Earth has so much mass, things within the Earth's atmosphere are pulled toward the planet. Therefore, when an object off of the ground is released, it falls toward the ground.
*Objects in free fall (not pushed) on Earth accelerate toward the ground at a rate of 9.8 m/s/s.
*Objects on other planets accelerate at different rates according to the mass of the planet--smaller planets have less acceleration because they have less gravity. Objects on larger planets fall at a greater rate of acceleration because those planets have more mass.
*The equation Fg = mg (the force of gravity = mass x acceleration due to gravity) can be used to calculate the weight of objects on various planets. On Earth, g = 9.8 m/s/s. Another word for the force of gravity is weight. Weight is measured in Newtons.
*Mass (the amount of matter making an object) never changes based on location. Weight (because it depends on gravity) DOES change depending on location. Therefore, you might have a mass of 75 kg, which will be the same no matter where you are. However, your weight might be about 750 Newtons on Earth, but it would be less than 750 N on the moon or a smaller planet. It would be much more than 750 N on any larger planet.
*Objects in free fall (not pushed) on Earth accelerate toward the ground at a rate of 9.8 m/s/s.
*Objects on other planets accelerate at different rates according to the mass of the planet--smaller planets have less acceleration because they have less gravity. Objects on larger planets fall at a greater rate of acceleration because those planets have more mass.
*The equation Fg = mg (the force of gravity = mass x acceleration due to gravity) can be used to calculate the weight of objects on various planets. On Earth, g = 9.8 m/s/s. Another word for the force of gravity is weight. Weight is measured in Newtons.
*Mass (the amount of matter making an object) never changes based on location. Weight (because it depends on gravity) DOES change depending on location. Therefore, you might have a mass of 75 kg, which will be the same no matter where you are. However, your weight might be about 750 Newtons on Earth, but it would be less than 750 N on the moon or a smaller planet. It would be much more than 750 N on any larger planet.
Air resistance is an important factor when thinking about falling objects. Because air molecules are in our atmosphere, it affects objects as they fall making it seem like lighter objects will fall slower than heavier objects of the same size. In a vacuum (where all air has been removed), all objects fall at the SAME speed. Don't believe me? Watch the video above!
PSc.1.2.2 Classify frictional forces into one of four types: static, sliding, rolling, and fluid.
Friction is the force that opposes motion. That means friction interferes with moving objects.
There are four types of friction: rolling friction, sliding friction, static friction, and fluid friction.
Watch the video below for examples of each type of friction!
There are four types of friction: rolling friction, sliding friction, static friction, and fluid friction.
Watch the video below for examples of each type of friction!
PSc.1.2.3 Explain forces using Newton’s three laws of motion.
Besides the "discovery" of gravity, Isaac Newton is best known for his 3 Laws of Motion.
1. An object in motion stays in motion (and an object at rest stays at rest) unless it is acted upon by another object.
Think about driving a car. If you are speeding down the highway and you take your foot off of the accelerator, the car still moves forward. However, it slowly begins to lose speed because it is being acted upon by the friction (from air resistance [fluid] and from the surface of the road against the tires [rolling]).
You can also think about a parked car. It's not going anywhere because of the friction between it and the ground [static] holding it in place. However, if another car crashes into that car, it will surge forward.
*Remember: this is also known as the law of inertia! Inertia is the resistance of a moving object to a change in its motion!
2. For two objects accelerating at the same rate, the object with the most mass will require the most force.
This law gives us the equation F=ma (force = mass x acceleration). If we are given any two of the variables, we can use this equation to solve for the missing variable. Remember, if you are given the mass and acceleration, you only have to MULTIPLY. If you are given the force and any other variable, you only have to DIVIDE.
3. Every action has an equal and opposite reaction.
This law is pretty self-explanatory. If an action occurs, and equal and opposite reaction also occurs. Think about a rocket waiting to take off from the surface of the Earth. Once the engines start and fire releases explosive force under the rocket, the rocket will be propelled upward with equal amounts of force.
1. An object in motion stays in motion (and an object at rest stays at rest) unless it is acted upon by another object.
Think about driving a car. If you are speeding down the highway and you take your foot off of the accelerator, the car still moves forward. However, it slowly begins to lose speed because it is being acted upon by the friction (from air resistance [fluid] and from the surface of the road against the tires [rolling]).
You can also think about a parked car. It's not going anywhere because of the friction between it and the ground [static] holding it in place. However, if another car crashes into that car, it will surge forward.
*Remember: this is also known as the law of inertia! Inertia is the resistance of a moving object to a change in its motion!
2. For two objects accelerating at the same rate, the object with the most mass will require the most force.
This law gives us the equation F=ma (force = mass x acceleration). If we are given any two of the variables, we can use this equation to solve for the missing variable. Remember, if you are given the mass and acceleration, you only have to MULTIPLY. If you are given the force and any other variable, you only have to DIVIDE.
3. Every action has an equal and opposite reaction.
This law is pretty self-explanatory. If an action occurs, and equal and opposite reaction also occurs. Think about a rocket waiting to take off from the surface of the Earth. Once the engines start and fire releases explosive force under the rocket, the rocket will be propelled upward with equal amounts of force.
Need a better picture? Watch the video below:
Test #2 Material:
PSc.3.1.1 Explain thermal energy and its transfer.
Substances that can easily transfer energy are called CONDUCTORS. Conductors are usually metals because they heat up or cool down quickly. They also transfer electricity very well. Think of all of the wires in your house: they are made of metals like copper and aluminum.
Substances that DO NOT transfer energy easily are called INSULATORS. Insulators include substances made of cloth or paper, pure water, and even air! These items heat up very slowly and once they do heat up, they typically hold onto the energy they have absorbed. Think about a thermos that you might use to keep your food hot or cold. Thermoses are shells made out of a variety of substances, but the key is that they have a layer of air between them that maintains the temperature of the food inside them. |
What does being a conductor actually mean?
*electrons move easily through the substance
*conductors have low specific heat (the amount of energy it takes for 1 gram of a substance to heat up by 1 degree C)
*insulators have a high specific heat (so it takes more energy to raise the temperature of 1 gram of substance by 1 degree C)
How can energy be transferred from once substance to another?
1. Conduction: energy is transferred directly from one substance that touches another
Ex) An ice cube on your table absorbs thermal energy from the table and melts as the molecules absorb the energy from the table and move faster (breaking bonds holding the ice cube together).
Ex 2) A pot is placed on a hot burner on the stove. The heat from the burner is transferred directly to the pot that is touching the burner and the pot gets hot. Also, water inside of the pot touches the hot pot and gets hot by touching the pot's surface.
2. Convection: energy is transferred through the movement of heated fluids (liquids and/or gases)
Ex) Heated air moves through an area and as a result temperature increases in that area. Our weather systems occur because of the movement of heated air. Warm air is less dense and spreads out toward cooler air masses.
3. Radiation: energy moves in the form of waves and does not need to travel through matter
Ex) Energy from the Sun travels all the way from the Sun to Earth in many forms (visible light, heat, and ultraviolet radiation among others). When you stand near a fire, you feel warm because the heat is radiating from the flames. The side of you facing a fire feels warmth, but your backside remains cool because the radiation cannot reach your backside.
*electrons move easily through the substance
*conductors have low specific heat (the amount of energy it takes for 1 gram of a substance to heat up by 1 degree C)
*insulators have a high specific heat (so it takes more energy to raise the temperature of 1 gram of substance by 1 degree C)
How can energy be transferred from once substance to another?
1. Conduction: energy is transferred directly from one substance that touches another
Ex) An ice cube on your table absorbs thermal energy from the table and melts as the molecules absorb the energy from the table and move faster (breaking bonds holding the ice cube together).
Ex 2) A pot is placed on a hot burner on the stove. The heat from the burner is transferred directly to the pot that is touching the burner and the pot gets hot. Also, water inside of the pot touches the hot pot and gets hot by touching the pot's surface.
2. Convection: energy is transferred through the movement of heated fluids (liquids and/or gases)
Ex) Heated air moves through an area and as a result temperature increases in that area. Our weather systems occur because of the movement of heated air. Warm air is less dense and spreads out toward cooler air masses.
3. Radiation: energy moves in the form of waves and does not need to travel through matter
Ex) Energy from the Sun travels all the way from the Sun to Earth in many forms (visible light, heat, and ultraviolet radiation among others). When you stand near a fire, you feel warm because the heat is radiating from the flames. The side of you facing a fire feels warmth, but your backside remains cool because the radiation cannot reach your backside.
Heat is a measure of thermal energy. Temperature is a measure of the average kinetic energy of particles of a substance. THEY ARE NOT THE SAME THING! Temperature is NOT a measure of how hot something is, just a measure of how fast the particles are moving! For example, room temperature is 77 degrees F (roughly 25 C). Most metals at that temperature are solids. Water is a liquid at that temperature. Oxygen is a gas at that temperature. We consider that a moderate temperature, but at that temperature, metals are already FROZEN and gases have already BOILED! Those are terms we usually attribute to cold and hot, yet to us--they are neither cold nor hot.
PSc.3.1.2 Explain the law of conservation of energy in a mechanical system in terms of kinetic energy, potential energy and heat.
The law of conservation of energy says that energy can neither be created nor destroyed only transferred.
Mechanical energy is the total energy in a system or the potential energy + kinetic energy within the system. Potential energy (aka gravitational potential energy) is the energy that is STORED in an object that is above the Earth's surface. Objects on Earth's surface have a gravitational potential energy of 0 because they are not off the ground. >The formula for calculating potential energy is: PE = mgh (or mass x acceleration due to gravity (9.8 m/s/s) x height). Kinetic energy is the energy of moving objects. If an object is not moving, it has 0 kinetic energy. Two objects of the same mass traveling at different speeds will have different amounts of kinetic energy--the one moving faster will have MORE. >The formula for calculating kinetic energy is: KE = 0.5mv^2 (one half x mass x velocity squared). |
In this example of the roller coaster:
Roller coaster car mass: 500 kg
Point W: 100 meters high, 0 m/s
>PE = mgh = (500) x (9.8) x (100) = 490,000 J
>KE = 0.5mv^2 = 0.5 x (500) x (0^2) = 0 J
Point X: 0 meters high, 44.3 m/s
>PE = mgh = (500) x (9.8) x (0) = 0 J
>KE = 0.5mv^2 = 0.5 x (500) x (44.3^2) = 490,000 J
Point Y: 40 meters high, 34.3 m/s
>PE = mgh = (500) x (9.8) x (40) = 196,000 J
>KE = 0.5mv^2 = 0.5 x (500) x (34.3^2) = 294,000 J
Point Z: 10 meters high, 42 m/s
>PE = mgh = (500) x (9.8) x (10) = 49,000 J
>KE = 0.5mv^2 = 0.5 x (500) x (42) = 441,000 J
*Note: In this example, we are assuming there is no friction on this roller coaster track. Therefore, the mechanical energy at each point on the roller coaster is the same. So because of the law of conservation of energy, that means ME = PE + KE.
Roller coaster car mass: 500 kg
Point W: 100 meters high, 0 m/s
>PE = mgh = (500) x (9.8) x (100) = 490,000 J
>KE = 0.5mv^2 = 0.5 x (500) x (0^2) = 0 J
Point X: 0 meters high, 44.3 m/s
>PE = mgh = (500) x (9.8) x (0) = 0 J
>KE = 0.5mv^2 = 0.5 x (500) x (44.3^2) = 490,000 J
Point Y: 40 meters high, 34.3 m/s
>PE = mgh = (500) x (9.8) x (40) = 196,000 J
>KE = 0.5mv^2 = 0.5 x (500) x (34.3^2) = 294,000 J
Point Z: 10 meters high, 42 m/s
>PE = mgh = (500) x (9.8) x (10) = 49,000 J
>KE = 0.5mv^2 = 0.5 x (500) x (42) = 441,000 J
*Note: In this example, we are assuming there is no friction on this roller coaster track. Therefore, the mechanical energy at each point on the roller coaster is the same. So because of the law of conservation of energy, that means ME = PE + KE.
Friction is the force the opposes motion. Because friction exists, some of the mechanical energy of a system is converted to HEAT as a waste product. In fact, when the roller coaster screeches to a stop, it does so because the friction is strong enough at the end of the coaster to convert all of the roller coaster car's energy into heat instead of motion!
Types of Friction we can encounter: 1. Rolling friction: friction that occurs when an object rolls across another (ex: wheels on the road) 2. Sliding friction: friction that occurs when an object slides across another (ex: pushing a box across the floor) 3. Fluid friction: friction that occurs from the contact of moving air or liquids with another object (ex: air resistance on a falling object) 4. Static friction: friction that occurs between nonmoving objects (an object sitting on a desk, like a book or lamp) |
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No matter what type of friction is occurring on an object, some of the object's energy is converted to HEAT. This is why brakes get hot when they are applied to moving wheels or a shuttle entering the Earth's atmosphere heats up greatly as the shuttle moves through the air.
PSc.3.1.3 Explain work in terms of the relationship among the applied force to an object, the resulting displacement of the object, and the energy transferred to an object.
Work is the energy used when force is applied to move an object. It can be calculated using the equation: W = F x d (force x distance). Work is measured in Newton meters, or Joules (like all other forms of energy).
In the picture to the right, notice Darin pushing Isaiah across the floor.
Isaiah's weight (750 N) is a force that Darin must overcome to move him. When he releases the chair, Isaiah rolls across the floor a distance of 12 meters. To figure out how much work Darin had to do: Work = Force x distance Work = 750 x 12 Work = 9000 J Gami also pushed Haleigh across the floor. If Haleigh weighed 300 N, and Gami pushed her 25 m across the floor, how much work did he do? Work = F d Work = 300 x 25 Work = 7500 J |
PSc.3.1.4 Explain the relationship among work, power and simple machines both qualitatively and quantitatively.
Power is simply how much work is done over a period of time. Power is measured in units called WATTS. To calculate power, all you have to do is divide the amount of work that is done by the time it took to do the work. The formula is P = W/t.
*Using the problems above, calculate how much power each "pusher" used:
> Darin did 9000 J of work. So if Darin did 9000 J of work in 5 seconds, then Power = 9000/5 = 1800 watts of power
>Gami did 7500 J of work. If Gami did 7500 J of work and Haleigh rolled across the floor for 12 seconds, how much power did he have?
Power = 7500/12 = 625 watts
>So we see that Darin had far more power in his push than Gami did--almost 3x the amount!
*Using the problems above, calculate how much power each "pusher" used:
> Darin did 9000 J of work. So if Darin did 9000 J of work in 5 seconds, then Power = 9000/5 = 1800 watts of power
>Gami did 7500 J of work. If Gami did 7500 J of work and Haleigh rolled across the floor for 12 seconds, how much power did he have?
Power = 7500/12 = 625 watts
>So we see that Darin had far more power in his push than Gami did--almost 3x the amount!
Work can be made easier for us by using machines. There are six simple machines: levers , pulleys, wheels and axles, inclined planes, wedges, and screws. These devices all require a greater distance for an object to be moved, but reduce the force needed. Therefore, the same amount of work is done, it's just much easier to do.
The simple machines are groups into categories based on what they do: 1. Levers (include actual levers, wheels and axles, and pulleys.) 2. Inclined planes (include actual inclined planes, wedges, and screws.) |
Machines make work easier because they produce mechanical advantage. Mechanical advantage is the number of times easier a machine makes the work. Therefore, there are no units of mechanical advantage.
There are two types of mechanical advantage: 1. ideal mechanical advantage (the MA that exists in a perfect world where there is no friction) 2. actual mechanical advantage (the real MA, including friction's effect) To calculate ideal mechanical advantage, all you have to do is divide the distance (effort) by the distance (resistance). IMA = d(effort)/d(resistance). The picture to the right shows the ideal mechanical advantage on an inclined plane. To calculate actual mechanical advantage, you divide the force (resistance) by the force (effort). AMA = F(resistance)/F(effort). However, because this isn't ideal, friction must be included. Suppose the boulder in the picture to the right had a weight of 500 N. If you only needed 200 N to roll the boulder up the ramp and the force of friction on the ramp was 50 N, then what was the actual mechanical advantage of the ramp? >First, add together the effort force that you used to roll the boulder with the force of friction of the ramp. (200 + 50) = 250 N. >Then, divide the resistance force by the effort force. (500 N/250 N) >The actual mechanical advantage is 2. |
All machines are measured according to how efficient they are--in other words, how well do they do their job without wasting energy?
Efficiency can be calculated two ways: 1. Work output/work input (work output divided by work input) x 100 2. Actual Mechanical Advantage/Ideal Mechanical Advantage (AMA divided by IMA) x 100 >We can look at the efficiency of the ramp used to move the boulder by comparing the AMA and IMA. >AMA/IMA = 2/4 = 0.5 x 100 = 50% >What that means is: 50% of the energy you are using to push the boulder up the ramp is actually being used to move the boulder. The other 50% is wasted as heat due to friction. |
When all is said and done, no machine, in reality, can have 100% efficiency. Why is that?
>to have 100% efficiency, that means no other forces (including friction) are acting on the machines
>friction acts on every machine--that's why they get hot when they are used!
>to have 100% efficiency, that means no other forces (including friction) are acting on the machines
>friction acts on every machine--that's why they get hot when they are used!
Test #3 Material: Waves, Electricity and Magnetism
PSc.3.2.1 Explain the relationships among wave frequency, wave period, wave velocity, amplitude, and wavelength through calculation and investigation.
Characteristics to know about waves:
1. Amplitude: the height of the wave from the resting position -This corresponds to how much energy is in the wave (in sound waves, higher amplitudes make LOUDER sound waves and lower amplitudes make SOFTER sound waves. -In light waves, high amplitudes make a brighter light and low amplitudes make a dull light. -The amount of energy in the wave (amplitude) is NOT affected by the wavelength, frequency OR velocity of the wave. 2. Crest: the top of the wave 3. Trough: the bottom of the wave 4. Wavelength: In transverse waves, it is the distance between successive crests or troughs (basically, the length of the wave that happens before it begins to repeat itself). -In longitudinal waves, the wavelength is the distance between two compressions or two rarefactions. >Compressions are the areas where the crests are pushed together tightly in a longitudinal wave. >Rarefactions are the areas where the crests are stretched farther apart in a longitudinal wave. 5. Frequency: how many times a wave repeats itself per second 6. Period: how long it takes (in seconds) for a wave to move past a certain point The period and frequency have an interesting relationship in that they are inverse of each other.
*To calculate the period when you know the frequency, just say period = 1/frequency. Frequencies are measured in Hertz (Hz). *To calculate the frequency when you know the period, just say frequency = 1/period. Periods are measured in seconds (s). An easy way of remembering the difference is to think about a clock. The frequency of the second-hand of the clock is 1/60 because it makes its full trip around the clock once every 60 seconds. The period of the second-hand of the clock is 60 seconds because the entire movement of the second hand takes 60 seconds to travel around the clock. |
Let's analyze the wave above!
-The wave has an amplitude of 2, because that is how high (or low) it travels from the resting position.
-The wavelength is also 2 meters. If we start at the origin, and trace the wave until it starts to repeat itself, that doesn't occur until the point (2,0). We could also measure from crest to next crest (0.5 --> 2.5), which is a difference of 2.
-The frequency of this wave is ALSO 2 Hz. In this diagram, the wave repeats itself twice. If we assume this entire wave occurred in one second, then that gives us the value of 2/1 Hz or 2 Hz.
-The period of this wave is 1/2 or 0.5 s. If this entire wave traveled through this point in one second, then 2 wavelengths occurred in 1 second. Remember, period = 1/frequency or 1/2!
Now that we know all of these details about the wave, we can calculate how fast the wave is actually moving! This is called wave velocity.
According to your reference table, velocity = wavelength x frequency.
Therefore, velocity = 2 meters x 2 Hertz. The wave velocity is 4 meters/second!
-The wave has an amplitude of 2, because that is how high (or low) it travels from the resting position.
-The wavelength is also 2 meters. If we start at the origin, and trace the wave until it starts to repeat itself, that doesn't occur until the point (2,0). We could also measure from crest to next crest (0.5 --> 2.5), which is a difference of 2.
-The frequency of this wave is ALSO 2 Hz. In this diagram, the wave repeats itself twice. If we assume this entire wave occurred in one second, then that gives us the value of 2/1 Hz or 2 Hz.
-The period of this wave is 1/2 or 0.5 s. If this entire wave traveled through this point in one second, then 2 wavelengths occurred in 1 second. Remember, period = 1/frequency or 1/2!
Now that we know all of these details about the wave, we can calculate how fast the wave is actually moving! This is called wave velocity.
According to your reference table, velocity = wavelength x frequency.
Therefore, velocity = 2 meters x 2 Hertz. The wave velocity is 4 meters/second!
PSc.3.2.2 Compare waves (mechanical, electromagnetic, and surface) using their characteristics.
Mechanical Waves
-need a medium (something for the wave to travel through) -sound waves (longitudinal) -particles move parallel to the waves as the waves travel through them -these waves travel FAST, but not super fast. |
Electromagnetic Waves
-need NO medium to travel (can travel through a vacuum/space) -all light waves (transverse) -if these waves DO pass through a medium, the waves move particles perpendicularly -these waves travel the FASTEST. |
Surface Waves
-need a medium -particles move in a circular motion Ex: the waves in the ocean, or the waves that cause the most damage during severe earthquakes -these waves travel SLOWLY |
PSc.3.2.3 Classify waves as transverse or compressional (longitudinal).
Transverse Waves are basically light waves.
They move particles at a 90 degree angle (perpendicularly) to their own motion.
Compressional or Longitudinal Waves are basically sound waves.
They move particles in the same direction (parallel), but back and forth as the wave passes through the particles.
Transverse Waves are basically light waves.
They move particles at a 90 degree angle (perpendicularly) to their own motion.
Compressional or Longitudinal Waves are basically sound waves.
They move particles in the same direction (parallel), but back and forth as the wave passes through the particles.
PSc.3.2.4 Illustrate the wave interactions of reflection, refraction, diffraction, and interference.
Type of Interaction:
1. Reflection:
2. Refraction:
3. Diffraction:
4. Interference:
Type of Interaction:
1. Reflection:
2. Refraction:
3. Diffraction:
4. Interference:
- a. Constructive:
- b. Destructive:
PSc.3.3.1 Summarize static and current electricity.
PSc.3.3.2 Explain simple series and parallel DC circuits in terms of Ohm’s law.
PSc.3.3.3 Explain how current is affected by changes in composition, length, temperature, and diameter of wire.
PSc.3.3.4 Explain magnetism in terms of domains, interactions of poles, and magnetic fields.
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PSc.3.3.5 Explain the practical application of magnetism.