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Heat/Temperature 1
Heat Temperature 2
Heat Transfer
Specific Heat
Random Questions
100
How are temperature and heat different?
Temperature is the average kinetic energy of a substance and heat is the transfer of energy from one substance to another.
100
How does heat flow?
From warmer area to colder area.
100
What is the difference between a conductor and an insulator? Give an example of each.
Conductor: allows heat to flow through it easily; metal Insulator: does not allow heat to flow through it easily; air, wood
100
DOUBLE JEOPARDY!!!!!! What is specific heat?
The amount of energy needed to raise 1 gram of a substance 1 degree Celsius.
100
DOUBLE JEOPARDY!!!!!!! In addition to the calorie and kilocalorie, what is another way scientists measure heat?
Joule
200
DOUBLE JEOPARDY!!!! How many joules ar in one calorie?
4.184 joules
200
Explain what happens when 2 objects make thermal contact.
Heat will flow from warmer object to colder object until thermal equilibrium is reached.
200
What type of heat transfer is responsible for ocean currents, such as the Gulf Stream?
convection
200
DOUBLE JEOPARDY!!!!! If a substance has a high specific heat, what does this tell you about the substance?
The substance must absorb/release a lot of energy to change its temperature.
200
What is radiation?
Energy that travels in electromagnetic waves?
300
DOUBLE JEOPARDY!!!!! What is a calorie?
The amount of energy required to raise 1 gram of water 1 degree Celsius.
300
Explain how a thermometer works in terms of thermal equilbrium.
Heat flow from mouth to thermometer until they reach the same temperature (thermal equilibrium). The thermometer will then read the same temperature as your body.
300
If I wanted to keep my coffee warm longer, should I use a white or black mug? Explain.
White because it is a bad absorber and therefore a bad emitter.
300
What is the formula for quantity of heat?
Q=m x c x change in temperature
300
Explain how a bimetallic strip works in bridges.
Made of two metals with different rates of expansion. Metal on top may expand more, causing the strip to bend downward when it heats and upward when it cools. This keeps the bridge from cracking.
400
You eat a bag of chips that contains 245 Calories. How many calories of heat would be released if the bag of chips were burned in a calorimeter?
2450 calories
400
DOUBLE JEOPARDY!!!! What happens to water as it is cooled from 4 degrees Celsius to 0 degrees Celsius?
It takes on a crystalline conformation and expands, becoming less dense.
400
Explain Newton's Law of Cooling.
The rate at which a substance cools (or warms) depends on the temperature difference between the substance and it surroundings. Bigger difference = faster rate of cooling (heating).
400
If 100 grams of water increases in temperature from 20 degrees Celsius to 80 degrees Celsius, what quantity of heat must the water have absorbed?
Q = m x c x change in temperature = 100 g x 1 cal/g C x 60 C = 6000 cal
400
DOUBLE JEOPARDY!!!! What is absolute zero?
0 degrees Kelvin; temp at which particles of a substance stop moving.
500
At what temperature does water boil and freeze on the Celsius scale and on the Fahrenheit scale?
Celsius: boils @ 100; freezes @ 0 Fahrenheit: Boils at 212; freezes @ 32
500
Explain why ice may never form on some large lakes in the winter even if the air around the lake is well below freezing.
The whole lake must reach 4 degrees celsius before any ice can form.
500
Explain the green house effect.
Short wavelength radiation from the sun is able to enter Earth's atmosphere. This energy is absorbed by Earth's surface and is reradiated in longer wavelengths which are trapped within the atmosphere by greenhouse gases, causing the temperature on Earth to increase.
500
An unknown mass of water releases 1000 calories of heat when decreasing its temperature from 50 degrees Celsius to 0 degrees Celsius. Find the mass of the water.
m= Q / (c x change in temperature) = 1000 cal / (1 cal/ g C x 50 C) =20 g
500
What type of energy would have a shorter wavelength - radiowaves or xrays? Why?
X-rays because they have more enrgy and therefore shorter wavelengths.