* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download ELAInteractiveVideo_G8
Classical mechanics wikipedia , lookup
Coriolis force wikipedia , lookup
Centrifugal force wikipedia , lookup
Equations of motion wikipedia , lookup
Rigid body dynamics wikipedia , lookup
Mass versus weight wikipedia , lookup
Fictitious force wikipedia , lookup
Modified Newtonian dynamics wikipedia , lookup
Classical central-force problem wikipedia , lookup
Jerk (physics) wikipedia , lookup
Newton's laws of motion wikipedia , lookup
Interactive Video Script Template Course Grade 6 Lesson Objective Semester A Unit 5 Lesson 8 Students will define the term acceleration. Students will describe the relationship between force and acceleration. CLIP A (Introduction) Visual <image> Audio Have you ever watched a car commercial where the car was advertised to go from zero to sixty in a specific amount of time? http://pixabay.com/en/lamborghini-brnoracing-car-618356/ <image> http://pixabay.com/en/gas-pedal-clutchpedal-clutch-397481/ You may have understood this advertisement to be describing the acceleration of the car, which is how most people think about acceleration. <image> http://pixabay.com/en/stopwatch-timetreadmill-race-259303/ But to a scientist, acceleration means more than just starting from zero and reaching a top speed. Acceleration means a change in velocity. <image> http://pixabay.com/en/curvy-road-signcrooked-road-sign-26514/ In fact, any change in velocity, or even a change in direction, results in acceleration! <image > http://pixabay.com/en/traffic-lights-lightarrow-444639/ That means that in addition to the car beginning to move from a complete stop, a car that stops at a traffic light accelerates, and a car that makes a turn at that light also accelerates! Question A Stem: What is acceleration? Answer Choices: A. Increase in speed B. Decrease in speed C. A change in velocity D. A change in motion Correct Response (C) (Video progresses to clip B) Incorrect Response (A, B, D) (Video progresses to clip E) CLIP B (DOK1) Visual Audio <image> The acceleration of an object is its change http://pixabay.com/en/abstract-abstraction- in velocity. acceleration-219915/ <image> http://pixabay.com/en/soccer-football-ballsport-playing-146218/ According to Newton’s first law of motion, if all of the forces on an object are balanced, if the object is not moving, it will stay at rest. And if it is moving, then it will continue its motion in the same direction. <image place side by side> http://pixabay.com/en/football-ball-soccersports-game-155528/ http://pixabay.com/en/arrow-up-downtraffic-downloads-145532/ If all the forces on an object are balanced, meaning a force in one direction has an equal force in the other direction, its acceleration will be zero. <image crop as indicated and place side by side> http://pixabay.com/en/arrows-red-set-updown-left-147741/ http://pixabay.com/en/football-ball-soccersports-game-155528/ The object would only accelerate if an unbalanced force, or force that is in an unequal magnitude and opposite direction than other forces, acts on the object. Question B Stem: If all forces on an object are balanced, what is the acceleration? A. It increases B. Depends on the direction of the force C. Zero D. Depends on the mass of the object Answer Choices: Correct Response (C) (Video progresses to clip C) Incorrect Response (A,B D) (Video progresses to clip F) CLIP C (Increased DOK2) Visual Audio <image> http://pixabay.com/en/road-sign-attentiondistrict-about-464661/ An unbalanced force can act on the object and change its speed or its direction, or both the rate of position change and direction. <image crop as shown> http://pixabay.com/en/accelerate-arrowup-direction-154141/ The acceleration of the object depends directly on the total force that acts on the object. As the total force increases, the acceleration increases. <image crop as shown> http://pixabay.com/en/arrows-blue-downpointing-35259/ The acceleration also depends on the mass of the object, but in an opposite way. As the mass increases, acceleration decreases. <image place side by side> http://pixabay.com/en/kilogram-massweight-10-gravity-147629/ http://pixabay.com/en/cross-box-deletemark-select-vote-27168/ http://pixabay.com/en/abstract-abstractionacceleration-164329/ The relationships between acceleration, force, and mass are described by Newton’s second law of motion… Scientists write this relationship as: Force equals mass times acceleration. Question C Stem: If the mass of an object increases, how is the acceleration affected? Answer Choices: A. Increases B. Decreases C. No change D. Goes to zero Correct Response (B) (Video progresses to clip D) Incorrect Response (A, C D) (Video progresses to clip G) CLIP D (Increased DOK3) Visual Audio <image crop as shown> http://pixabay.com/en/arrow-direction-turnset-left-36877/ Like force and velocity, acceleration has a magnitude and direction, so it is a vector. <image place side by side > http://pixabay.com/en/push-pushing-movemoving-action-150175/ http://pixabay.com/en/arrow-right-bluehanddrawn-310633/ Because acceleration is directly related to the force, it will be in the same direction as the acceleration. So if we know the direction of the acceleration, we know the direction of the force that caused it. <image place side by side > http://pixabay.com/en/push-pushing-movemoving-action-150175/ http://pixabay.com/en/letters-abcalphabet-journal-font-451474/ Because acceleration is directly related to force, it changes with the same proportion as force. So if the force acting on an object is doubled, the acceleration also doubles. <image place side by side> http://pixabay.com/en/kilogram-massweight-10-gravity-147629/ http://pixabay.com/en/half-half-time-halflife-time-145736/ However, the opposite effect happens for the mass. If the mass of an object is doubled while the force stays the same, the acceleration of the object is reduced by one-half. Question D Stem: If the force acting on an object is reduced by one-half, what happens to its acceleration? Answer Choices: A. Reduced by one-half B. Doubles C. Triples D. Zero Correct Response (A) (Video progresses to Success Alert) Incorrect Response (B, C, D) (Video progresses to clip H) CLIP E (Remedial 1) Visual <image> Audio Imagine you are watching a car race on a straight track. The cars are driving very fast, but would you be surprised to learn that if they aren’t changing their direction or speed, they aren’t accelerating? http://www.morguefile.com/archive/display /218403 <image> http://pixabay.com/en/stopwatch-timetreadmill-race-259303/ That’s because, by definition, acceleration is a change in velocity. Remember, velocity is the rate at which an object changes its position. <image> http://pixabay.com/en/winding-road-roadtravel-553481/ That means that in this case, the car must either speed up, slow down, or change its direction by turning the wheel, in order to accelerate. <image> http://pixabay.com/en/road-sign-asphaltroad-sign-90390/ Acceleration includes any change in velocity, even a decrease in the rate of the position, is considered to be acceleration! Question E Stem: Which of the following situations are considered to be acceleration? Answer Choices: A. A car turns left at a constant rate B. You pedal your bicycle at a constant rate in a straight line C. A book is sitting on a table D. A person is walking on a straight path at a constant rate Correct Response (A) (Video progresses to clip B) Incorrect Response (B, C, D) (Video progresses to clip F) CLIP F (Remedial 2) Visual <image> http://pixabay.com/en/speedometertachometer-gauge-mph-153399/ Audio Any time an object changes its velocity, it is accelerating. If velocity remains constant, the object is not accelerating. <image> http://pixabay.com/en/the-ball-stadionfootball-the-pitch-488700/ Newton’s first law of motion explains inertia and states that an object at rest will remain that way and an object that is moving will continue to move at the same rate and direction. <image place side by side> http://pixabay.com/en/arrows-up-downgreen-159565/ http://pixabay.com/en/the-ball-stadionfootball-the-pitch-488700/ According to inertia, an object with forces that have equal forces in opposite directions, or balanced forces, will have zero acceleration. <image> If a ball is sitting on the ground, there are equal forces between the ball and the Earth. If you add an unbalanced force by kicking the ball, you will cause it to accelerate. http://www.morguefile.com/archive/display /857633 Question F Stem: What is a quantity that only tells value and not direction? Answer Choices: A. B. C. D. Vector Systemic Total Average Correct Response (A) Incorrect Response (B, C, D) (Video progresses to clip C) (Video progresses to Intervention Alert, bringing students back to clip B) CLIP G (Remedial 3) Visual <image> Audio The rate at which an object moves in a particular direction can be changed if an unbalanced force acts on it. http://pixabay.com/en/catcher-baseballyouth-sport-ball-632974/ <image> The unbalanced force will cause the object to accelerate, which will depend on the total force acting on the object. As the force increases, the acceleration will increase also. http://pixabay.com/en/baseball-sportsplate-home-97898/ <image> http://pixabay.com/en/ball-base-fieldobject-sport-315494/ The mass of the object also affects the acceleration, but in the opposite direction. As the object’s mass increases, the acceleration decreases. <image place side by side-make middle image (x) smaller> http://pixabay.com/en/kilogram-massweight-10-gravity-147629/ http://pixabay.com/en/cross-box-deletemark-select-vote-27168/ http://pixabay.com/en/abstract-abstractionacceleration-164329/ Newton’s second law of motion explains this relationship between mass, force, and acceleration. Mathematically, we can explain it by saying force is equal to mass times acceleration. Question G Stem: If the total force acting on an object increases, how is the acceleration affected? Answer Choices: A. B. C. D. Increases Decreases No changes Goes to zero Correct Response (A) (Video progresses to clip D) Incorrect Response ( B, C,D) (Video progresses to clip F) CLIP H (Remedial 4) Visual Audio <image crop as indicate> http://pixabay.com/en/arrows-road-streetasphalt-500751/ Like velocity and force, acceleration has direction of movement too, so we call it a vector. <image> http://pixabay.com/en/golf-arrow-golf-ball549230/ Acceleration is directly related to the force, so the direction of the force. The direction is inversely proportional, however. If the force comes from the right, the acceleration will be to the left. <image place side by side> http://pixabay.com/en/golf-arrow-golf-ball- The acceleration will also change if the force changes. If the force doubles, the 549230/ http://pixabay.com/en/letters-abcalphabet-journal-font-451474/ acceleration will also double. <image place side by side> http://pixabay.com/en/kilogram-massweight-10-gravity-147629/ http://pixabay.com/en/half-half-time-halflife-time-145736/ Mass also affects the acceleration, but in the opposite direction. So, if the mass is tripled, the acceleration will be reduced by one-third. Question H Stem: If the mass of an object is reduced by one half, what happens to its acceleration? Answer Choices: A. B. C. D. Reduced by one-half Doubles Triples Zero Correct Response (B) (Video progresses to Success Alert) Incorrect Response (A, C, D) (Video progresses to clip G)