Podcast
Questions and Answers
In physics, what is the formula for work?
In physics, what is the formula for work?
Force x time x cos θ
If a person pushes an object with twice the force for twice the distance, the person does _________ the work.
If a person pushes an object with twice the force for twice the distance, the person does _________ the work.
4X the work
The unit of work is the __________.
The unit of work is the __________.
Joule
Power is defined as the ___________.
Power is defined as the ___________.
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The amount of potential energy possessed by an elevated object is equal to the amount of ___________ .
The amount of potential energy possessed by an elevated object is equal to the amount of ___________ .
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Kinetic energy formula ___________.
Kinetic energy formula ___________.
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How much farther will a car traveling at 20 km/s skid than the same car traveling at 10 km/s?
How much farther will a car traveling at 20 km/s skid than the same car traveling at 10 km/s?
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An arrow in a bow has 20 J of potential energy. Assuming no loss of energy, how much kinetic energy will it have after it has been shot?
An arrow in a bow has 20 J of potential energy. Assuming no loss of energy, how much kinetic energy will it have after it has been shot?
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Energy is changed from one form to another with no net loss or gain? True or False
Energy is changed from one form to another with no net loss or gain? True or False
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As a pendulum swings back and forth, where does it have the most KE and PE?
As a pendulum swings back and forth, where does it have the most KE and PE?
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Which requires more work: lifting a 50-kg sack vertically 1 meters or lifting a 5-kg sack vertically 10 meters?
Which requires more work: lifting a 50-kg sack vertically 1 meters or lifting a 5-kg sack vertically 10 meters?
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When a car's speed triples, its kinetic energy ______________.
When a car's speed triples, its kinetic energy ______________.
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A ball is thrown into the air. When it returns to its original level after encountering air resistance, its kinetic energy is MORE, LESS, OR SAME?
A ball is thrown into the air. When it returns to its original level after encountering air resistance, its kinetic energy is MORE, LESS, OR SAME?
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A person on a roof throws one ball downward and an identical ball upward at the same speed. The ball thrown downward hits the ground with 140 J of kinetic energy. Ignoring air friction, with how much kinetic energy does the second ball hit the ground?
A person on a roof throws one ball downward and an identical ball upward at the same speed. The ball thrown downward hits the ground with 140 J of kinetic energy. Ignoring air friction, with how much kinetic energy does the second ball hit the ground?
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How many joules of work are done on a box when a force of 25 N east pushes it 3 m east?
How many joules of work are done on a box when a force of 25 N east pushes it 3 m east?
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How much power is required to do 40 J of work on an object in 5 seconds?
How much power is required to do 40 J of work on an object in 5 seconds?
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How much work is done on a 60 N box that you carry horizontally across a 6-m room?
How much work is done on a 60 N box that you carry horizontally across a 6-m room?
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How much power is expended if you lift a 60 N crate 10 meters in 1 second?
How much power is expended if you lift a 60 N crate 10 meters in 1 second?
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Suppose a moving car has 3000 J of kinetic energy. If the car's speed doubles, then have _________ more than 3000 J.
Suppose a moving car has 3000 J of kinetic energy. If the car's speed doubles, then have _________ more than 3000 J.
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It takes 80 J to push a large box 16 m across a floor. Assuming the push is in the same direction as the move, what is the magnitude of the force on the box?
It takes 80 J to push a large box 16 m across a floor. Assuming the push is in the same direction as the move, what is the magnitude of the force on the box?
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A frictionless inclined plane is 6.0 m long and rests on a wall that is 2.0 m high. How much force is needed to push a block of ice weighing 300.0 N up the plane?
A frictionless inclined plane is 6.0 m long and rests on a wall that is 2.0 m high. How much force is needed to push a block of ice weighing 300.0 N up the plane?
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Total Mechanical energy can be in the form of what two types of energy?
Total Mechanical energy can be in the form of what two types of energy?
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If an object has a mass 2kg and is lifted 5 meters off the ground how much PE does it have?
If an object has a mass 2kg and is lifted 5 meters off the ground how much PE does it have?
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How much KE will it have when it is held at the 5 meters?
How much KE will it have when it is held at the 5 meters?
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If the object is dropped and it falls to 1 mm off the ground. How much PE will it have basically?
If the object is dropped and it falls to 1 mm off the ground. How much PE will it have basically?
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If it has a velocity of 9.49 m/s after falling 5 meters, how much KE will it have?
If it has a velocity of 9.49 m/s after falling 5 meters, how much KE will it have?
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Determine the work energy that is lost due to Air resistance in this case.
Determine the work energy that is lost due to Air resistance in this case.
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Study Notes
Key Physics Concepts
- Work: Force multiplied by the distance and cosine of the angle between force and displacement.
- Formula: Work = Force × Distance × cosθ
- Units: Joules (J)
- Power: Rate of doing work.
- Formula: Power = Work / Time
- Units: Watts (W)
- Kinetic Energy (KE): Energy of motion.
- Formula: KE = 1/2 * m * v² (where m = mass and v = velocity)
- Potential Energy (PE): Energy stored due to position.
- Formula: PE = m * g * h (where m = mass, g = acceleration due to gravity, and h = height)
Energy Transformations
- Conservation of Energy: Energy can neither be created nor destroyed; it can only be transformed from one form to another.
- Potential to Kinetic Energy: An example, a falling object changes its potential energy to kinetic energy as it falls.
- Mechanical Energy: The total energy of an object is the sum of its kinetic and potential energy
- Other forms of energy: Heat, light, chemical etc
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Description
This quiz covers fundamental concepts in physics, focusing on work, power, kinetic energy, and potential energy. It also explores the transformations of energy and the principle of conservation of energy. Test your understanding of the essential formulas and units involved in these key topics!
