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Questions and Answers
What is the net force on a box pushed to the right with 50 N of force while being pushed to the left with 20 N of force?
What is the net force on a box pushed to the right with 50 N of force while being pushed to the left with 20 N of force?
30 N to the right
What two quantities are necessary for a vector quantity?
What two quantities are necessary for a vector quantity?
direction and magnitude
What can be said about the forces acting on an object that is at rest?
What can be said about the forces acting on an object that is at rest?
are opposite in direction, are equal in magnitude, and have a vector sum of zero
How much tension is there in a vertical rope that holds a 20-N bag of apples at rest?
How much tension is there in a vertical rope that holds a 20-N bag of apples at rest?
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What is the acceleration of an object in free fall at Earth's surface?
What is the acceleration of an object in free fall at Earth's surface?
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A car is traveling with constant velocity. This means that _______.
A car is traveling with constant velocity. This means that _______.
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A stone is dropped off a cliff and is in free fall. Every second that the stone is falling, its acceleration _______.
A stone is dropped off a cliff and is in free fall. Every second that the stone is falling, its acceleration _______.
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By how much would a speedometer reading increase every second for an object in free fall?
By how much would a speedometer reading increase every second for an object in free fall?
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As an object freely falls, its ___ increases.
As an object freely falls, its ___ increases.
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At the end of two seconds of free fall, an object released from rest will have a speed of:
At the end of two seconds of free fall, an object released from rest will have a speed of:
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When she hikes a distance of 1 km in a time of one-half hour, her average speed is?
When she hikes a distance of 1 km in a time of one-half hour, her average speed is?
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An object is pulled with two forces, 10 N northward and 15 N southward. The direction of the net force is to the?
An object is pulled with two forces, 10 N northward and 15 N southward. The direction of the net force is to the?
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Where is your weight greater: on Earth or on the Moon? How about your mass?
Where is your weight greater: on Earth or on the Moon? How about your mass?
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Mass is a measure of _______.
Mass is a measure of _______.
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If you pull on a box with a force of 5 N and your teacher pulls on the same box with a force of 5 N in the opposite direction, the net force on the box is _______.
If you pull on a box with a force of 5 N and your teacher pulls on the same box with a force of 5 N in the opposite direction, the net force on the box is _______.
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An object is at rest. The forces acting on the object _______.
An object is at rest. The forces acting on the object _______.
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What is the acceleration of an object in free fall at Earth's surface?
What is the acceleration of an object in free fall at Earth's surface?
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A free-falling object has a speed of 30 m/s at one instant. Exactly 2 seconds later, its speed will be?
A free-falling object has a speed of 30 m/s at one instant. Exactly 2 seconds later, its speed will be?
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Compared with a 1-kg block of solid iron, a 2-kg block of solid iron has twice as much _______.
Compared with a 1-kg block of solid iron, a 2-kg block of solid iron has twice as much _______.
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It is important to know that the term inertia refers to _______.
It is important to know that the term inertia refers to _______.
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What is the net force that acts on a 10-N freely falling object?
What is the net force that acts on a 10-N freely falling object?
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A heavy parachutist has a greater terminal speed compared with a lighter parachutist with the same size parachute because the heavier person _______.
A heavy parachutist has a greater terminal speed compared with a lighter parachutist with the same size parachute because the heavier person _______.
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Newton's second law of motion links force, acceleration, and _______.
Newton's second law of motion links force, acceleration, and _______.
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Whenever one object exerts a force on a second object, the second object exerts a force on the first that _______.
Whenever one object exerts a force on a second object, the second object exerts a force on the first that _______.
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When two horizontal forces are exerted on the car, 250 N forward and 230 N backward, what is the amount of acceleration?
When two horizontal forces are exerted on the car, 250 N forward and 230 N backward, what is the amount of acceleration?
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What is Newton's first law?
What is Newton's first law?
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What is Newton's second law?
What is Newton's second law?
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What is Newton's third law?
What is Newton's third law?
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What is the net force acting on a falling 1-kg ball if it encounters 2 N of air resistance?
What is the net force acting on a falling 1-kg ball if it encounters 2 N of air resistance?
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Is inertia a property of matter or a force of some kind?
Is inertia a property of matter or a force of some kind?
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Newton's second law of motion links force, acceleration, and _______.
Newton's second law of motion links force, acceleration, and _______.
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If you are learning to juggle it would be good to slow the ball's acceleration. You can do this by using ______.
If you are learning to juggle it would be good to slow the ball's acceleration. You can do this by using ______.
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Study Notes
Net Force
- Net force on a box pushed with 50 N right and 20 N left is 30 N right.
- Forces acting on a stationary object are equal and opposite, resulting in a vector sum of zero.
Vector Quantities
- Vector quantities require both direction and magnitude for their complete description.
Tension
- Tension in a vertical rope holding a 20-N object at rest is 20 N.
Free Fall
- Acceleration of an object in free fall at Earth's surface is 9.8 m/s².
- Free-falling stone’s acceleration remains constant while its velocity increases each second by 9.8 m/s.
- A free-fall object will have its speed increase by 9.8 m/s each second.
Motion Consistency
- An object with constant velocity moves in a straight line with no change in speed.
Comparing Mass and Weight
- A 2-kg block of iron has no similarities compared to a 1-kg block in terms of density or volume, but it has double the mass.
- Mass remains constant regardless of location; weight is greater on Earth compared to the Moon.
Inertia and Force
- Inertia refers to matter's resistance to changes in motion.
- If equal forces act on a box from opposite directions (5 N each), the net force is 0 N.
Dynamics of Forces
- An object experiences a net force of 10 N while freely falling, which matches its weight.
- Total net force on a car from 250 N forward and 230 N backward results in 20 N backward.
Newton's Laws of Motion
- Newton’s first law describes inertia; an object at rest remains at rest unless acted upon.
- Newton's second law relates force, mass, and acceleration.
- Newton's third law states that every action has an equal and opposite reaction.
Falling Objects and Resistance
- A falling object with 2 N of air resistance has a net force of 7.8 N.
- Heavier parachutists have greater terminal speeds since they must fall faster to equalize weight with air resistance.
Acceleration and Motion
- Speed readings for a free-falling object will yield a speed of 50 m/s two seconds after reaching 30 m/s.
- Average speed for a 1 km hike in 0.5 hours is 2 km/h.
Juggling Mechanics
- To slow the ball’s acceleration while learning to juggle, use heavier balls.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your understanding of fundamental physics concepts with these flashcards. Each card provides a question on topics such as net force and vector quantities. Perfect for students looking to reinforce their knowledge in physics.
