REVIEW FOR HEAT AND TEMPERATURE UNIT

REVIEW FOR HEAT AND TEMPERATURE UNIT

SCIENCE 7GCMS

PART ONE—MEASURING TEMPERATURE

1. Which of the following are typical ways that we can estimate the temperature of an item (how hot or cold it is)?

A. By touching the itemB. By the color of the light an item gives off (how

much glow).C. By the sound the item makes (popping of popcorn).D. All the above are typical means of estimating

temperature.E. Only A and B are typical.• Answer is E

Question 2)Which of the following is the most reliable means of measuring temperature?

A. Looking at the color of the object.B. Touching the object with your hand.C. Using a thermometer to measure the

temperature of the object.D. Listening to the object.• Answer• C

Question 3)Which of the following measuring scales identifies “absolute zero” as 0o?

A. The Fahrenheit scaleB. The Centigrade scaleC. The Celsius scaleD. The Kelvin scale• Answer• D

Question 4)Which of the following statements describe how Anders Celsius designed his temperature scale?

A. He had to decide on an unit and standard for comparision.B. He used the “degree” as the unit of temperature on his scale.C. He based his standards for comparison on the properties of

water (most abundant liquid on earth).D. He assigned a value of 100 degrees to the temperature at

which water boils at sea level.E. He assigned a value of zero degrees for the temperature in

which water freezes at sea level.F. All the above are correct statements about how Anders

Celsius designed his temperature scale.• Answer• F

Question 5)Which of the following statements are characteristics of a thermocouple?

A. A thermocouple can be used to measure very high temperatures that would cause the liquid to boil in a traditional thermometer.

B. A thermocouple can be used to accurately measure a very cold temperature.

C. A thermocouple is made of wires (each a different metal) twisted together.

D. When the twisted wire tips are heated, a small electrical current is generated.

E. The temperature determines the amount of electrical current generated.

F. Thermocouples are used to turn a switch or valve on or off if the temperature changes (pilot light for a gas furnace).

• Answer• All but B are correct.

Question 6)Which of the following statements are characteristics of a bimetallic strip?

A. A bimetallic strip is made of two different metals joined firmly together.

B. When the strip is heated, one of the metals expands more than the other causing the strip to coil more tightly.

C. When the strip is cooled, the same metal that expanded rapidly will now contract rapidly causing the strip to uncoil.

D. Bimetallic strips can only be used in temperatures less than 100o C.

E. Bimetallic strips are often used to control furnaces, air conditioners and refrigerators.

• Answer• All but D are correct.

Question 7)Which of the following statements are characteristics of a recording thermometer?

A. Recording thermometers are sometimes called thermographs.

B. A special pen can record the changes in temperature measured by a bimetallic strip.

C. The pen marks are recorded on paper attached to a slow moving drum that can measure changes for a week.

D. The recording thermometer requires constant monitoring by the user to record change in temperature.

• Answer• All but D are correct.

Question 8)Which of the following statements are characteristics of a infrared thermogram or how it measures temperature?

A. Anything that is warmer than absolute zero gives off infrared radiation (IR)

B. Infrared radiation can be photographed with special film.C. Infrared radiation can be detected by electronic sensors that display

images on LCD screens.D. You can actually see infrared radiation with your own eyes (un-

aided).E. The color or the brightness of the infrared image shows the

temperature of the object.F. Infrared Thermograms can be used to measure extremely hot

surfaces.• Answer• All but D are correct.

Question 9)Which of the following are good thermal conductors, that is they are excellent at transferring heat?

A. GoldB. CopperC. IronD. WoodE. All the above are excellent heat conductors.F. Only A, B, and C are excellent heat conductors.• Answer• F

Question 10)Which of the following are poor thermal conductors, that is they are called heat insulators?

A. Neoprene RubberB. SteelC. PlasticD. WoodE. All the above are poor heat conductors.F. Only A, C, and D are poor heat conductors.• Answer• F

Question 11)Which of the following statements are typically true about radiation?

A. Radiation is the transfer of energy without any movement of matter.

B. Radiant energy (electromagnetic radiation—EMR) behaves like a wave.

C. Radiant energy can travel through empty space, air, glass and other transparent materials.

D. Examples of EMR waves used today include radio waves, microwaves, and X-rays.

E. EMR waves can be absorbed or reflected by objects.F. EMR waves travel very slowly (slower than the speed of sound).• Answer• All but F are correct

Question 12)Which of the following statements are typically true about conduction?

A. Conduction is the transferring of thermal energy through direct collisions between particles.

B. Particles that are closest to the heat source absorb the energy and begin to move more rapidly.

C. Faster moving particles collide/bump into neighbouring particles increasing their energy and motion.

D. Conduction is consistent through all forms of matter (the thermal energy is transfer at the same rate, regardless of the material).

E. Poor heat conductors are called heat insulators (they slow down the transfer of thermal energy).

Answer All but D are correct.

Question 13)Which of the following statements are typically true about convection?

A. Thermal energy can be transferred by fluids (materials that can be poured or that flow from place to place).

B. In convection, a warm fluid moves from place to place carrying the thermal energy with it.

C. Warm fluids tend to rise while colder fluids fall (this causes convection currents).

D. Convection can be explained by the fact that energy transfers from lower energy substances to higher energy substances.

E. Convection ovens use forced air to increase the heating capacity of your stove allowing you to cook food quicker than with a conventional oven.

• Answer• All but D are correct.

Question 14)Which of the following statements are ideas that apply to the particle model of matter?

A. All substances are made of tiny particles too small to be seen.

B. The particles are always in motion—vibrating, rotating and moving from place to place (gases and liquids).

C. The particles have spaces between them.D. The motion in the particles decreases when the

temperature increases.E. The motion in the particles decreases when the

temperature decreases.• Answer• All but D are correct (increased temperature increases

motion).

Answer True or False for Each of the following statements:

• Materials in a solid state keep their shape and size.• True• Solids have a definite shape and volume but can be compressed into a

smaller space.• False• Materials in a liquid state have a definite size (volume) but no fixed

shape.• True• Liquids take the shape of their containers and can be compressed.• False• Gases have no definite shape or volume and can be easily compressed

into a smaller space.• True• Contraction is the decrease in volume and occurs when objects cool.• True

Answer True or False for Each of the following statements:

• Pressure can alter the boiling point and freezing temperature of water.

• True• The lower the pressure the higher the boiling point temperature for

water.• False• The higher the pressure the lower the melting point temperature

for ice.• True• Impurities in water can change the boiling point and freezing point

temperatures for water.• True

Answer True or False for Each of the following statements:

• Absolute zero is approximately -273o Celsius.• True• Body temperature is approximately 37o Celsius.• True• Water freezes at 0o Celsius.• True• Water boils at 100o Celsius.• True• Energy can not be created or destroyed. It can only be

transformed from one type to another or passed from one object to another.

• True (law of conservation of energy)

Answer True or False for Each of the following statements:

• Changes in energy only happen when there is a difference of energy (between to objects).

• True• Energy is always transferred in the same

direction.• True• Energy is always transferred from a high-

energy source to a low-energy source.• True

Answer True or False to each statement about changes in state:

• Changes in heat can cause changes in state (solid, liquid, gas or in the rare cases plasma).

• True• During a phase change (solid to a liquid) the total energy of a

substance does not change (increase or decrease).• False• During a phase change (liquid to a gas) the temperature of the

substance does not increase it stays constant.• True• Although the particles do not increase or decrease in speed

during a phase change the change in arrangement of the particles causes a total increase or decrease in energy to occur.

• True

LINKS TO HEAT AND TEMPERATURE ANIMATIONS ON THE INTERNET

• http://www.bbc.co.uk/schools/ks2bitesize/science/materials/• http://www.worsleyschool.net/science/files/state/changes.html• FIRST FOUR ONLY AT SKOOOL SITE• http://lgfl.skoool.co.uk/keystage3.aspx?id=64• http://www.usborne-quicklinks.com/ca/ca_entity_pages/ca_sel

ect_link.asp?lang=ca&lvl=2&menu=s100&id=1204&From=110&To=111

• (THE ABOVE LINK HAS MULTIPLE SITES AND A FEW IMAGES)• http://www.yteach.co.uk/index.php/resources/bromine_collisio

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