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An object that has kinetic energy must be?
An object that has kinetic energy must be?
moving
A cannonball has more kinetic energy than the recoiling cannon from which it is fired because the force on the ball?
A cannonball has more kinetic energy than the recoiling cannon from which it is fired because the force on the ball?
acts over a longer distance.
If you do work on a skateboard loaded with friends in one-third the usual time, you expend?
If you do work on a skateboard loaded with friends in one-third the usual time, you expend?
three times the usual power.
A roller skate at rest may have?
A roller skate at rest may have?
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The work you do when pushing a shopping cart twice as far while applying twice the force is?
The work you do when pushing a shopping cart twice as far while applying twice the force is?
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A motorcycle moving at 50 km/h skids 10 m with locked brakes. How far will it skid with locked brakes when traveling at 150 km/h?
A motorcycle moving at 50 km/h skids 10 m with locked brakes. How far will it skid with locked brakes when traveling at 150 km/h?
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A light aluminum ball and a heavy lead ball of the same size roll down an incline. When they are halfway down the incline, they will have identical?
A light aluminum ball and a heavy lead ball of the same size roll down an incline. When they are halfway down the incline, they will have identical?
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Two identical golf carts move at different speeds. The faster cart has twice the speed and therefore has?
Two identical golf carts move at different speeds. The faster cart has twice the speed and therefore has?
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The work you do when pushing a shopping cart a given distance while applying twice as much force is?
The work you do when pushing a shopping cart a given distance while applying twice as much force is?
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A bicycle that travels four times as fast as another when braking to a stop will skid?
A bicycle that travels four times as fast as another when braking to a stop will skid?
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A car's engine is 20% efficient. When cruising, the car encounters an average retarding force of 1000 N. If the energy content of fuel is 40 megajoules per liter, how many kilometers per liter does the car achieve?
A car's engine is 20% efficient. When cruising, the car encounters an average retarding force of 1000 N. If the energy content of fuel is 40 megajoules per liter, how many kilometers per liter does the car achieve?
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After rolling halfway down an incline, a marble's kinetic energy is?
After rolling halfway down an incline, a marble's kinetic energy is?
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Which task requires more work?
Which task requires more work?
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A melon is projected into the air with 100 J of kinetic energy in the presence of air resistance. When it returns to its initial level its kinetic energy is?
A melon is projected into the air with 100 J of kinetic energy in the presence of air resistance. When it returns to its initial level its kinetic energy is?
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A ball rolling down an incline has its maximum potential energy at?
A ball rolling down an incline has its maximum potential energy at?
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A bicycle that travels twice as fast as another when braking to a stop will skid?
A bicycle that travels twice as fast as another when braking to a stop will skid?
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A 1-kg ball dropped from 2 m rebounds only 1.5 m after hitting the ground. The amount of energy converted to heat is about?
A 1-kg ball dropped from 2 m rebounds only 1.5 m after hitting the ground. The amount of energy converted to heat is about?
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A hydraulic jack is used to lift objects such as automobiles. If the input force is 200 N over a distance of 1 meter, the output force over a distance of 0.1 meter is ideally?
A hydraulic jack is used to lift objects such as automobiles. If the input force is 200 N over a distance of 1 meter, the output force over a distance of 0.1 meter is ideally?
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The work done in pushing a TV set a distance of 2 m with an average force of 20 N is?
The work done in pushing a TV set a distance of 2 m with an average force of 20 N is?
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A hydraulic press has its input piston depressed 20 centimeters while the output piston is raised 1 centimeter. A 1-newton input can lift a load of?
A hydraulic press has its input piston depressed 20 centimeters while the output piston is raised 1 centimeter. A 1-newton input can lift a load of?
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A jack system will increase the potential energy of a heavy load by 1000 J with a work input of 2000 J. The efficiency of the jack system is?
A jack system will increase the potential energy of a heavy load by 1000 J with a work input of 2000 J. The efficiency of the jack system is?
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If the speed of a bicycle is reduced to half before skidding to a stop, it will skid?
If the speed of a bicycle is reduced to half before skidding to a stop, it will skid?
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Both a 50-kg sack lifted 2 meters from the ground and a 25-kg sack lifted 4 meters in the same time. The power expended in raising the 50-kg sack is?
Both a 50-kg sack lifted 2 meters from the ground and a 25-kg sack lifted 4 meters in the same time. The power expended in raising the 50-kg sack is?
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A moving object has?
A moving object has?
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The power required to exert 4-N force over 3 meters in 2 seconds is?
The power required to exert 4-N force over 3 meters in 2 seconds is?
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When a drawn bow of potential energy 40 J is fired, the arrow will ideally have a kinetic energy?
When a drawn bow of potential energy 40 J is fired, the arrow will ideally have a kinetic energy?
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Neglecting air resistance, Sammy Smarts on a high ladder releases a ball that strikes the ground with 100 J of kinetic energy. If he were to instead throw the ball straight upward, it will soon reach the ground with a kinetic energy of?
Neglecting air resistance, Sammy Smarts on a high ladder releases a ball that strikes the ground with 100 J of kinetic energy. If he were to instead throw the ball straight upward, it will soon reach the ground with a kinetic energy of?
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A 1000-kg car and a 2000-kg car are hoisted to the same height. Raising the more massive car requires?
A 1000-kg car and a 2000-kg car are hoisted to the same height. Raising the more massive car requires?
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Impulse involves the time that a force acts, whereas work involves the?
Impulse involves the time that a force acts, whereas work involves the?
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A clerk can lift cylindrical packages 1 meter vertically, or can roll them up a 2-meter-long ramp to the same elevation. With the ramp, the applied force required is about?
A clerk can lift cylindrical packages 1 meter vertically, or can roll them up a 2-meter-long ramp to the same elevation. With the ramp, the applied force required is about?
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The unit kilowatt-hour is a unit of?
The unit kilowatt-hour is a unit of?
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About 40 J is required to push a crate 4 m across a floor. If the push is in the same direction as the motion of the crate, the force on the crate is about?
About 40 J is required to push a crate 4 m across a floor. If the push is in the same direction as the motion of the crate, the force on the crate is about?
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The power expended doing 100 J of work in 50 s is?
The power expended doing 100 J of work in 50 s is?
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A crate of grapes lifted 10 meters gains 200 J of potential energy. If the same crate is instead lifted 20 meters, its gain in potential energy is?
A crate of grapes lifted 10 meters gains 200 J of potential energy. If the same crate is instead lifted 20 meters, its gain in potential energy is?
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If an all-electric car has kinetic energy, then it also must have?
If an all-electric car has kinetic energy, then it also must have?
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A machine puts out 100 watts of power for every 1000 watts put into it. The efficiency of the machine is?
A machine puts out 100 watts of power for every 1000 watts put into it. The efficiency of the machine is?
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Strictly speaking, more fuel is consumed by your car if the air conditioner, headlights, or even a radio is turned on.
Strictly speaking, more fuel is consumed by your car if the air conditioner, headlights, or even a radio is turned on.
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Acrobat Bart at the circus drops vertically onto the end of a see-saw, with his partner Art equidistant from the fulcrum at the other end. Art is propelled straight upward a distance twice that of Bart's dropping distance. Neglecting inefficiencies we see?
Acrobat Bart at the circus drops vertically onto the end of a see-saw, with his partner Art equidistant from the fulcrum at the other end. Art is propelled straight upward a distance twice that of Bart's dropping distance. Neglecting inefficiencies we see?
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No work is done by gravity on a bowling ball that rolls along a bowling alley because?
No work is done by gravity on a bowling ball that rolls along a bowling alley because?
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The bob of a simple pendulum has its maximum kinetic energy at the?
The bob of a simple pendulum has its maximum kinetic energy at the?
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Which has greater kinetic energy?
Which has greater kinetic energy?
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The amount of work done on a heavy box carried by Nellie across a room at a constant speed?
The amount of work done on a heavy box carried by Nellie across a room at a constant speed?
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One kilowatt-hour represents?
One kilowatt-hour represents?
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A melon is tossed straight upward with 100 J of kinetic energy. If air resistance is negligible the melon will return to its initial level with a kinetic energy of?
A melon is tossed straight upward with 100 J of kinetic energy. If air resistance is negligible the melon will return to its initial level with a kinetic energy of?
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The work you do when pushing a shopping cart twice as far while applying the same force is?
The work you do when pushing a shopping cart twice as far while applying the same force is?
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When you and your snowboard are in motion, which of the following can be zero?
When you and your snowboard are in motion, which of the following can be zero?
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The ram of a pile driver drops onto the top of an iron beam, driving it partway into the ground. The distance that the beam sinks into the ground depends on the?
The ram of a pile driver drops onto the top of an iron beam, driving it partway into the ground. The distance that the beam sinks into the ground depends on the?
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Relative to an initial height, an object raised twice as high has a gravitational potential energy?
Relative to an initial height, an object raised twice as high has a gravitational potential energy?
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If a Ping-Pong ball and a golf ball both move in the same direction with the same amount of kinetic energy, the speed of the Ping-Pong ball must be?
If a Ping-Pong ball and a golf ball both move in the same direction with the same amount of kinetic energy, the speed of the Ping-Pong ball must be?
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A primary difference between momentum and kinetic energy is?
A primary difference between momentum and kinetic energy is?
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A block of ice sliding down an incline has half its maximum kinetic energy?
A block of ice sliding down an incline has half its maximum kinetic energy?
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Two identical arrows, one with twice the speed of the other, are fired into a bale of hay. Compared with penetration of the slow arrow, the faster arrow penetrates?
Two identical arrows, one with twice the speed of the other, are fired into a bale of hay. Compared with penetration of the slow arrow, the faster arrow penetrates?
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A circus diver drops from a high pole into water far below. When he is halfway down?
A circus diver drops from a high pole into water far below. When he is halfway down?
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A 2500-N pile-driver ram falls 10 m and drives a post 0.1 m into the ground. The average impact force on the ram is?
A 2500-N pile-driver ram falls 10 m and drives a post 0.1 m into the ground. The average impact force on the ram is?
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When wind encounters a wind turbine that produces energy, wind speed on the downside of the blades is?
When wind encounters a wind turbine that produces energy, wind speed on the downside of the blades is?
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Which requires the most amount of work by the brakes of a car?
Which requires the most amount of work by the brakes of a car?
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An object has gravitational potential energy due to its?
An object has gravitational potential energy due to its?
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When Joshua brakes his speeding bicycle to a stop, kinetic energy is transformed to?
When Joshua brakes his speeding bicycle to a stop, kinetic energy is transformed to?
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Danny Diver weighs 500 N and steps off a diving board 10 m above the water. Danny hits the water with kinetic energy of?
Danny Diver weighs 500 N and steps off a diving board 10 m above the water. Danny hits the water with kinetic energy of?
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Two identical particles move toward each other, one twice as fast as the other. Just before they collide, one has a kinetic energy of 25 J and the other 50 J. At this instant their total kinetic energy is?
Two identical particles move toward each other, one twice as fast as the other. Just before they collide, one has a kinetic energy of 25 J and the other 50 J. At this instant their total kinetic energy is?
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Two identical arrows, one with twice the kinetic energy of the other, are fired into a bale of hay. Compared with penetration of the slow arrow, the faster arrow penetrates?
Two identical arrows, one with twice the kinetic energy of the other, are fired into a bale of hay. Compared with penetration of the slow arrow, the faster arrow penetrates?
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A 2-kg box of taffy candy has 40 J of potential energy relative to the ground. Its height above the ground is?
A 2-kg box of taffy candy has 40 J of potential energy relative to the ground. Its height above the ground is?
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A 2-kg ball is held 4 m above the ground. Relative to the ground its potential energy is?
A 2-kg ball is held 4 m above the ground. Relative to the ground its potential energy is?
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A toy elevator is raised from the ground floor to the second floor in 20 seconds. The power needed using 1000 J of work, is?
A toy elevator is raised from the ground floor to the second floor in 20 seconds. The power needed using 1000 J of work, is?
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A ball rolling down an incline has its maximum kinetic energy at?
A ball rolling down an incline has its maximum kinetic energy at?
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Tomatoes have a higher specific heat capacity than dough. This means that when you bite into a hot pizza?
Tomatoes have a higher specific heat capacity than dough. This means that when you bite into a hot pizza?
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The specific heat capacity is highest for substances that absorb or release large quantities of heat for correspondingly?
The specific heat capacity is highest for substances that absorb or release large quantities of heat for correspondingly?
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A substance that heats up relatively slowly has a?
A substance that heats up relatively slowly has a?
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Aluminum has a higher specific heat capacity than iron. This means that for equal masses of aluminum and iron, the metal that heats more quickly when the same amount of heat is applied is?
Aluminum has a higher specific heat capacity than iron. This means that for equal masses of aluminum and iron, the metal that heats more quickly when the same amount of heat is applied is?
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Place a 1-kilogram block of iron at 40°C into 1 kilogram of water at 20°C and the final temperature of the two becomes?
Place a 1-kilogram block of iron at 40°C into 1 kilogram of water at 20°C and the final temperature of the two becomes?
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Heat energy travels from an object with a high?
Heat energy travels from an object with a high?
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Which unit represents the most energy?
Which unit represents the most energy?
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Compared to a giant iceberg, a hot cup of coffee has?
Compared to a giant iceberg, a hot cup of coffee has?
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The quantity of heat that a substance can transfer relates to its?
The quantity of heat that a substance can transfer relates to its?
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Which temperature scale has the smallest sized degrees?
Which temperature scale has the smallest sized degrees?
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Temperature is most closely related to molecular?
Temperature is most closely related to molecular?
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The amount of heat needed to raise the temperature of 1 gram of water by 1°C is?
The amount of heat needed to raise the temperature of 1 gram of water by 1°C is?
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If the specific heat capacity of water were lower than it is, a nice hot bath would be a?
If the specific heat capacity of water were lower than it is, a nice hot bath would be a?
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Room temperature on the Kelvin scale is about?
Room temperature on the Kelvin scale is about?
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The fact that desert sand is very hot in the day and very cold at night is evidence that the specific heat capacity of sand is relatively?
The fact that desert sand is very hot in the day and very cold at night is evidence that the specific heat capacity of sand is relatively?
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When 10 grams of hot water cool by 1°C, the amount of heat given off is?
When 10 grams of hot water cool by 1°C, the amount of heat given off is?
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A temperature difference of 10 Celsius degrees is also equal to a temperature difference of 10 on the?
A temperature difference of 10 Celsius degrees is also equal to a temperature difference of 10 on the?
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The air in your room is composed of molecules that have?
The air in your room is composed of molecules that have?
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Heat energy is measured in units of?
Heat energy is measured in units of?
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In which is the temperature greater?
In which is the temperature greater?
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Which temperature scales have equal sized degrees?
Which temperature scales have equal sized degrees?
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Aluminum has a specific heat capacity more than twice that of copper. Place equal masses of aluminum and copper wire in a flame and the one to undergo the fastest increase in temperature will be?
Aluminum has a specific heat capacity more than twice that of copper. Place equal masses of aluminum and copper wire in a flame and the one to undergo the fastest increase in temperature will be?
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The fact that a thermometer 'takes its own temperature' illustrates?
The fact that a thermometer 'takes its own temperature' illustrates?
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Pour a liter of water at 40°C into a liter of water at 20°C and the final temperature of the two becomes?
Pour a liter of water at 40°C into a liter of water at 20°C and the final temperature of the two becomes?
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Pour two liters of water at 40°C into one liter of water at 20°C and the final temperature of the two becomes?
Pour two liters of water at 40°C into one liter of water at 20°C and the final temperature of the two becomes?
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One of water's interesting thermal properties is that when heated it takes a relatively?
One of water's interesting thermal properties is that when heated it takes a relatively?
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A substance that heats up relatively quickly has a?
A substance that heats up relatively quickly has a?
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When you touch a cold piece of ice with your finger, energy flows?
When you touch a cold piece of ice with your finger, energy flows?
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When you touch a hot potato with your finger, energy flows?
When you touch a hot potato with your finger, energy flows?
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If the specific heat of water were lower than it is, ponds in the cold winter would be?
If the specific heat of water were lower than it is, ponds in the cold winter would be?
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Which of the following normally warms up fastest when heat is applied?
Which of the following normally warms up fastest when heat is applied?
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If the specific heat capacity of water were lower than it is, a watermelon in a picnic cooler would cool in a?
If the specific heat capacity of water were lower than it is, a watermelon in a picnic cooler would cool in a?
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A substance that cools down faster than others has a?
A substance that cools down faster than others has a?
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The white-hot sparks from a 4th-of-July-type sparkler that strike your skin transfer?
The white-hot sparks from a 4th-of-July-type sparkler that strike your skin transfer?
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The moderate temperatures of islands throughout the world have much to do with water's?
The moderate temperatures of islands throughout the world have much to do with water's?
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Study Notes
Kinetic Energy and Work
- An object with kinetic energy is moving.
- A cannonball possesses more kinetic energy than the recoiling cannon due to the force acting over a longer distance.
- Performing work on a skateboard loaded with friends in one-third the usual time results in three times the typical power exerted.
- A roller skate at rest contains potential energy.
- Pushing a shopping cart twice as far while applying double the force leads to four times the work done.
- A motorcycle traveling at 150 km/h will skid 90 m with locked brakes, much more than at a lower speed.
- Identical objects rolling down an incline have varying forms of energy; their energies are not identical halfway down.
- A faster golf cart moving at double speed has four times the kinetic energy compared to a slower one.
- If a bicycle travels twice as fast when skidding, it will skid sixteen times farther.
- A car with a 20% efficient engine experiences a retarding force of 1000 N, achieving 8 km per liter of fuel.
Energy Transformation and Conservation
- After rolling halfway down an incline, a marble has the same kinetic energy as its initial potential energy.
- A melon projected with 100 J of kinetic energy loses energy due to air resistance upon returning to its initial height.
- Potential energy is maximized at the top of an incline and is transformed fully to kinetic at the bottom.
- A 1-kg ball dropped from 2 m rebounds, converting about more than 2.0 J of energy to heat.
- Using a hydraulic jack, the output force is significantly higher (2000 N) compared to the input force (200 N) over different distances.
Calculating Power and Efficiency
- The work done in pushing a television for 2 m with an average force of 20 N equals 40 J.
- Hydraulic systems can amplify force, allowing for heavy loads to be lifted effectively.
- The efficiency of a jacking system that raises 1000 J of potential energy with 2000 J of work input is 50%.
- If a speed decreases to half, the distance skidded will be reduced to one-fourth compared to its original distance.
Work and Energy in Various Contexts
- The gravitational potential energy of an object depends on its height from the ground.
- The relationship between momentum and kinetic energy shows that while momenta can cancel, kinetic energy cannot.
- Impulse involves the force acting over time, while work will consider the distance the force acts upon.
- Kinetic energy transformation occurs during braking; kinetic energy is transformed to heat.
Thermal Properties and Heat Transfer
- Specific heat capacity dictates how substances respond to heat; materials like aluminum heat up quickly compared to others like water.
- Heat energy naturally transfers from higher to lower temperatures, balancing thermal equilibrium.
- Room temperature is approximately 300 K on the Kelvin scale.
- A lower specific heat capacity means a substance will change temperature more quickly.
- The amount of heat required to raise the temperature of 1 g of water by 1°C is 4.19 Joules.
Practical Implications of Heat and Energy
- The unique thermal properties of water contribute to moderate island temperatures due to its high specific heat capacity.
- The temperature difference between scales like Celsius and Kelvin is interchangeable for small differences.
- The energy flow, when touching objects at different temperatures, is always from the hotter to the cooler object.
- Ponds would be more likely to freeze if water had a lower specific heat capacity, illustrating the importance of water's thermal properties in environmental contexts.
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Description
This quiz focuses on key concepts related to kinetic energy, exploring definitions and principles through flashcards. Test your understanding of how kinetic energy applies in various scenarios, such as moving objects and the effects of force and distance.
