Podcast
Questions and Answers
What is the net force needed to give a 10-kg package an acceleration of 6.0 m/s²?
What is the net force needed to give a 10-kg package an acceleration of 6.0 m/s²?
60 N
Find the examples of scalar quantities. Check all that apply!
Find the examples of scalar quantities. Check all that apply!
What kind of path would the planets follow if their attraction to the Sun no longer existed?
What kind of path would the planets follow if their attraction to the Sun no longer existed?
The planets would move in straight-line paths.
What is the acceleration when a 21-N net force is exerted on a 3.0-kg cart?
What is the acceleration when a 21-N net force is exerted on a 3.0-kg cart?
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What is Newton's first law of motion?
What is Newton's first law of motion?
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How hard does a wall push back when you push on it with a force of 37 N?
How hard does a wall push back when you push on it with a force of 37 N?
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What is your acceleration while pushing on the wall if your mass is 54 kg?
What is your acceleration while pushing on the wall if your mass is 54 kg?
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What is the acceleration of a freely falling 10-N object?
What is the acceleration of a freely falling 10-N object?
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What is the force of friction when dragging a block at a steady speed while exerting a force of 5 N?
What is the force of friction when dragging a block at a steady speed while exerting a force of 5 N?
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Do action and reaction forces act in succession or simultaneously?
Do action and reaction forces act in succession or simultaneously?
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Find the examples of vector quantities. Check all that apply.
Find the examples of vector quantities. Check all that apply.
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What is the ranking from greatest to least for the masses of three 100-kg boxes?
What is the ranking from greatest to least for the masses of three 100-kg boxes?
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Rank the weights of a 100-kg box on Jupiter, Earth, and the Moon from greatest to least.
Rank the weights of a 100-kg box on Jupiter, Earth, and the Moon from greatest to least.
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What is Newton's third law of motion?
What is Newton's third law of motion?
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What force does a board exert on a hand during a karate chop that delivers a force of 3000 N?
What force does a board exert on a hand during a karate chop that delivers a force of 3000 N?
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Rank the amount of friction from greatest to least between a crate and the floor.
Rank the amount of friction from greatest to least between a crate and the floor.
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Why do the cannonball and cannon have different accelerations despite equal forces acting on them?
Why do the cannonball and cannon have different accelerations despite equal forces acting on them?
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Newton's second law states: The acceleration produced by a net force on an object is directly proportional to the net force, is in the same direction as the net force, and is inversely proportional to the _____ of the object.
Newton's second law states: The acceleration produced by a net force on an object is directly proportional to the net force, is in the same direction as the net force, and is inversely proportional to the _____ of the object.
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Express Newton's second law using symbols.
Express Newton's second law using symbols.
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What happens to the clay blobs when Dr. Hewitt turns around?
What happens to the clay blobs when Dr. Hewitt turns around?
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Why do the clay blobs behave this way when Dr. Hewitt turns?
Why do the clay blobs behave this way when Dr. Hewitt turns?
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How can you move a letter floating in a bowl of soup closer to you by rotating the bowl?
How can you move a letter floating in a bowl of soup closer to you by rotating the bowl?
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Why do the alphabet letters behave this way when you rotate the bowl?
Why do the alphabet letters behave this way when you rotate the bowl?
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Which ball has greater acceleration as it drops toward the ground?
Which ball has greater acceleration as it drops toward the ground?
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Which ball do you predict will reach the ground first?
Which ball do you predict will reach the ground first?
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Which ball will be traveling faster upon hitting the ground?
Which ball will be traveling faster upon hitting the ground?
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Find the examples of vector quantities again. Check all that apply.
Find the examples of vector quantities again. Check all that apply.
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Find the examples of scalar quantities again. Check all that apply.
Find the examples of scalar quantities again. Check all that apply.
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What will the scale read if you replace a 56-g magnet with a more powerful one that has the same mass?
What will the scale read if you replace a 56-g magnet with a more powerful one that has the same mass?
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Where will the more powerful magnet hover compared to the original magnet?
Where will the more powerful magnet hover compared to the original magnet?
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Why doesn't a heavy object accelerate more than a light object when freely falling?
Why doesn't a heavy object accelerate more than a light object when freely falling?
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What test tells us if a moving object is in equilibrium?
What test tells us if a moving object is in equilibrium?
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What factors affect the amount of air resistance on a wing suit flyer?
What factors affect the amount of air resistance on a wing suit flyer?
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Which changes would make it more likely for a ball to hit both the white can and the green can in a video demonstration?
Which changes would make it more likely for a ball to hit both the white can and the green can in a video demonstration?
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How would increasing the mass of an elephant affect its acceleration if force applied is kept constant?
How would increasing the mass of an elephant affect its acceleration if force applied is kept constant?
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How would increasing the applied force on an elephant affect its acceleration?
How would increasing the applied force on an elephant affect its acceleration?
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What force bends your fingers when you push against a wall?
What force bends your fingers when you push against a wall?
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How many forces are required for a single interaction?
How many forces are required for a single interaction?
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An object cannot remain at rest unless which condition holds?
An object cannot remain at rest unless which condition holds?
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What is the acceleration of a cart on an inclined plane that gains 5.4 m/s each 1.7 s?
What is the acceleration of a cart on an inclined plane that gains 5.4 m/s each 1.7 s?
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What will the spring scale read in an elevator if it is moving upward at constant speed with a 100-kg mass?
What will the spring scale read in an elevator if it is moving upward at constant speed with a 100-kg mass?
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Who falls faster when wearing the same-size parachute—a heavy person or a light person?
Who falls faster when wearing the same-size parachute—a heavy person or a light person?
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What provides the force that propels a rocket?
What provides the force that propels a rocket?
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What is needed to accelerate a system?
What is needed to accelerate a system?
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What net force does a sliding crate experience when you exert a force of 125 N and the friction is 115 N?
What net force does a sliding crate experience when you exert a force of 125 N and the friction is 115 N?
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When two vectors are at right angles to each other, the resultant is greater than either of the vectors separately.
When two vectors are at right angles to each other, the resultant is greater than either of the vectors separately.
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What is the acceleration of a falling object that has reached its terminal velocity?
What is the acceleration of a falling object that has reached its terminal velocity?
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As mass is added to a pushed object, what happens to its acceleration?
As mass is added to a pushed object, what happens to its acceleration?
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What is the acceleration of a 1.3-kg object in free fall?
What is the acceleration of a 1.3-kg object in free fall?
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Rank the terminal velocities of parachutists A (40 kg), B (75 kg), and C (50 kg) from fastest to slowest.
Rank the terminal velocities of parachutists A (40 kg), B (75 kg), and C (50 kg) from fastest to slowest.
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Rank the order in reaching the ground for parachutists A (40 kg), B (75 kg), and C (50 kg) from longest to shortest.
Rank the order in reaching the ground for parachutists A (40 kg), B (75 kg), and C (50 kg) from longest to shortest.
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Is acceleration directly proportional or inversely proportional to force?
Is acceleration directly proportional or inversely proportional to force?
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Is acceleration directly proportional or inversely proportional to mass?
Is acceleration directly proportional or inversely proportional to mass?
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Which force diagram correctly displays all horizontal forces exerted on the cart by the surrounding air?
Which force diagram correctly displays all horizontal forces exerted on the cart by the surrounding air?
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What is the net force needed to give an 8.0-kg package an acceleration of 8.0 m/s²?
What is the net force needed to give an 8.0-kg package an acceleration of 8.0 m/s²?
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What is the acceleration of a 0.60-kg object in free fall?
What is the acceleration of a 0.60-kg object in free fall?
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What is the acceleration of a cart on an inclined plane that gains 6.4 m/s each 1.7 s?
What is the acceleration of a cart on an inclined plane that gains 6.4 m/s each 1.7 s?
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Study Notes
Newton's Laws of Motion and Forces
- Newton's second law defines the relationship between net force (Fnet), mass (m), and acceleration (a) as Fnet = ma. A 10 kg object needing 6 m/s² acceleration requires a net force of 60 N.
- Newton's first law states an object remains at rest or in uniform motion unless acted upon by a nonzero force.
- Newton's third law highlights that for every action, there is an equal and opposite reaction force.
- A net force of 21 N acting on a 3.0 kg cart results in an acceleration of 7 m/s².
- In equilibrium, the net force acting on an object is zero; this means a constant velocity indicates no change in state.
Scalars and Vectors
- Scalars include quantities such as speed, volume, and time, which only have magnitude.
- Vectors, on the other hand, include velocity, force, and acceleration, having both magnitude and direction.
- The force of friction opposing motion equals the applied force at constant speed; for instance, 5 N of applied force results in 5 N of friction.
Motion and Gravity
- If planetary attraction to the sun ceased, planets would travel in straight-line paths.
- A freely falling object experiences an acceleration of approximately 10 m/s² due to gravity.
- Terminal velocity occurs when the weight of a falling object equals air resistance, leading to zero acceleration.
Experiments and Observations
- When pushing against a wall, the force exerted back on the hands is equal (e.g., 37 N).
- The force experienced by a moving object is influenced by its mass and the net forces acting on it.
- In free fall, all objects accelerate equally regardless of mass, as demonstrated by 1.3 kg and 0.60 kg stones both experiencing 10 m/s².
Equipment and Measurement
- The acceleration of an object on an inclined plane can be calculated; for instance, a cart increasing by 5.4 m/s over 1.7 s yields an acceleration of 3.2 m/s².
- In an upward-moving elevator at constant speed, the force measured on a scale would remain unchanged (e.g., 18 N).
Practical Applications of Forces
- To maintain acceleration in any system, an external force is necessary; increasing the mass of an object being pushed reduces its acceleration.
- When comparing multiple objects under the same conditions (e.g., parachutists of varying weights), heavier objects tend to fall faster, while lighter objects fall slower due to differences in terminal velocity.
Conclusion
- Understanding the principles of force, motion, and the distinction between vector and scalar quantities is essential in mastering the foundational concepts of physics.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your knowledge of key concepts in Physics Chapter 3 with these flashcards. Topics covered include Newton's second law, net force calculations, and scalar quantities. Perfect for students looking to reinforce their understanding of these fundamental principles.
