Download Conduction – heat movement through the vibration of molecules in a

Up to 3 bonus points possible if all questions are answered!
Science 10 Academic
Unit Test
48
Name_________________________
Part A Selected Response: Select the correct answer for each question by
CIRCLING only the correct LETTER. (10 points)
1. Which surface absorbs the most solar energy?
A) a snowy field
C) a glacier
B) a polar ice cap
D) a flowing river
2. If you burn your hand by touching the handle of a hot pot, what is the method of heat
transfer?
A) conduction
C) radiation
B) convection
D) vaporization
3. Which type of radiant energy is not a component of solar energy?
A) infrared
C) microwaves
B) ultraviolet
D) visible light
4. Why does a body of water change temperature slowly in comparison to land?
A) Soil has a much lower heat of vaporization
B) Soil has a lower value of heat capacity (c) than water
C) Soil reflects more light than water
D) Soil conducts the warmth far below the surface
5. If the weather today is cold, with a clear blue sky and light breezes, what is the most
likely explanation?
A) a high pressure system
C) a cold front
B) a low pressure system
D) a warm front
6. Which of the following latitudes will have the fastest surface speed due to Earth’s
rotation?
A) North Pole
C) Tropic of Cancer
B) Temperate zone
D) Equator
7. Which of the following describes a layer of featureless clouds that create rain?
A) altocumulus
C) cirronimbus
B) cumulostratus
D) nimbostratus
8. Which of the following clouds create thunderstorms?
A) altostratus
C) nimbocumulus
B) cumulostratus
D) stratus
Page 1 of 8
9. Which of the following factors will determine if a prevailing wind is a westerly or an
easterly?
A) It depends on whether the wind is in the northern or southern hemisphere.
B) It depends on whether the wind is moving toward the pole or the equator.
C) It depends on the direction of the jet stream.
D) Prevailing winds are always westerlies.
10. The weather in Bridgewater on a particular day is very warm and humid, but the
weather in Moncton , New Brunswick (to the West) is very cool and dry. What
change should you expect within the next day or two?
A) No change because the weather in Moncton will not affect Bridgewater.
B) A warm front is approaching so be prepared for a long period of steady rain.
C) A cold front is approaching so be prepared for a thunderstorm
D). A low pressure system is approaching so be prepared for strong winds.
Part B Selected Response: Write the correct letter in each blank to match the
definition or description with the vocabulary term. (7 points)
11. Match the heat transfer definition by writing the letter next to the correct term. (4 pts)
a) Heat energy is passed by rising currents of gas
or liquids.
b) The amount of energy needed to heat one gram
of a pure substance by one degree Celsius = c.
c) Heat energy passes through empty space or clear
materials as wave energy.
d) Radiant energy does not pass through a material,
but is “stopped” and converted to heat energy.
e) Radiation does not pass through a material, but
is turned back in the opposite direction.
f) Heat energy is passed from molecule to another
by vibrations in solids.
g) The amount of energy absorbed in boiling one
gram of a pure liquid.
h) The amount of energy released in freezing one
gram of a pure liquid.
Page 2 of 8
__d___ absorption
__f___ conduction
__a___ convection
__h___ heat of fusion
__g___ heat of vaporization
__c____ radiation
__e___ reflection
__b___specific heat capacity
12. Match the description by writing the correct letter next to the vocabulary term. (3 pts)
a) A factor that can change the density of water in
oceans, creating surface currents.
b) A factor that can change the direction of ocean
currents
c) A strong current of air (wind) high in the
atmosphere
d) An increase in the ocean’s water level due to a
strong low pressure system.
e) A change in the direction of a current or air
mass due to differences in the Earth’s speed of
rotation at different latitudes.
f) The source of energy for hurricanes
__c___jet stream
___b__ shape of continents
__a___salinity
_f____heat of condensation
___d___storm surge
__e___Coriolis Effect
Part C Constructed Response: Answer in brief, complete sentences. Use diagrams
where appropriate. (19 pts)
13. Explain how water’s high heat of vaporization prevents its temperature from changing
easily. (1 pt)
When water warms, it loses a lot of heat to evaporation.
14. Describe how and when an onshore breeze is created. (2 pts)
Warm air rises over land during the day and cool air blows in from the ocean to
replace it in a convection current.
15. What two factors are needed for a surface current to form? (2 pt)
Low density (warm or less saline) water and prevailing (constant) winds that blow
in one direction.
Page 3 of 8
16. Describe two of the three factors control the direction of ocean currents. (2 pts)
Ocean currents’ directions are controlled by the direction of prevailing winds, the
Coriolis Effect (turns currents to the right in the north, to the left in the south), and
the shape of continents (currents will follow the coastline).
17. Describe the temperature pattern found in most gyres and how it impacts climates on
the west side of ocean basins. (3 pts)
Gyres are warm on the Western side and cool on the Eastern side. Warm, humid
air masses form over the western side, bringing warm, rainy weather to the coastal
areas.
18. Describe the “normal” pattern of winds and surface water temperatures in the Pacific
Ocean and describe the changes that occur during an El Niño. (3 pts)
Normally in the Pacific, the Trade winds blow strongly toward the west, pushing
warm water towards Australia and Tahiti (west). Along the coast of Peru, cold
waters are drawn up from the bottom to replace the warm water (upwelling).
During El Nino, the Trade winds weaken, the warm waters spread eastward and
upwelling are prevented.
19. Describe three ways that a hurricane causes damage to coastal cities. (3 points)
Rising water due to storm surge cause flooding, and heavy rains and winds
damage buildings and landscape.
Flooding and erosion result from water damage and winds damage building.
Page 4 of 8
20. Sketch a cold front (as seen from the side) including cloud formation, and explain the
typical pattern of weather (temperature and precipitation) you would experience as a
cold front passes over you. (3 points)
As the front moves over you, there would be
a short period of heavy rain, thunderstorm
or snow. After the front passes, the weather
will be much cooler.
Part D Calculations: Show COMPLETE calculations and answer in brief, complete
sentences. Include correct units and round your answers appropriately. (7 points)
21. On a cool spring evening, the air temperature is 8ºC and the dew point is 4ºC. What
is the relative humidity? (1 pt)
Use the HUMIDITY TABLE!!! 8C humidity = 6.8 g/kg 4C humidity = 5.1 g/kg
RH = 5.1 / 6.8 x 100% = 75%
22. If the air temperature is 22ºC and the relative humidity is 45.9%, what is the actual
humidity and the dew point temperature (to the nearest degree)? (1pt)
22C humidity = 17.0 g/kg
RH
49.5% = x/17.0 x 100%
x = 7.8 g/kg
Use Humidity table: 7.8 is the humidity for 10C (dew point temperature)
Page 5 of 8
23. 500g of water is heated from 20ºC to 85 ºC. How much heat is needed? (3 pts)
G: m =500g, water c = 4.18 J/gC change in T = 85 – 20 =65C
R: find heat (Q)
A: Q = mcΔT
S Q = 500 x 4.18 x 65 = 135 850J
P 136 000 J of heat is needed
24. How much heat is needed to completely evaporate 20 g of water?(2 pts)
G: m = 20g evaporation ΔH = +2260J/g
R: find Q
A: Q = m ΔH
S: Q = 20 x 2260 = 45 200J
P: It takes 45 000J to evaporate 20g.
Page 6 of 8
Part E Science Literacy –Read the article carefully BEFORE answering! Answer in
brief, complete sentences. (8 points)
Arctic Melt
Jan. 9, 2008
Earth's North and South Poles are famous for being cold and icy. Last year, however, the amount
of ice in the Arctic Ocean fell to a record low.
Normally, ice builds in Arctic waters around the North Pole each winter and shrinks during the
summer. But for many years, the amount of ice left by the end of summer has been declining.
Since 1979, each decade has seen an 11.4 percent drop in end-of-summer ice cover. Between
1981 and 2000, ice in the Arctic lost 22 percent of its thickness—becoming 1.13 meters (3.7 feet)
thinner.
Last summer, Arctic sea ice reached its skimpiest levels yet. By the end of summer 2007, the ice
had shrunk to cover just 4.2 million square kilometers. That's 38 percent less area than the
average cover at that time of year. And it's a whopping 23 percent below the previous record low,
which was set just 2 years ago. This continuing trend has scientists concerned.
There may be several reasons for the ice melt, says Jinlun Zhang, an oceanographer at the
University of Washington in Seattle. Unusually strong winds blew through the Arctic last summer.
The winds pushed much of the ice out of the central Arctic, leaving a large area of thin ice and
open water.
Scientists also suspect (but haven't yet documented) that fewer clouds cover the Arctic now than
in the past. Clearer skies allow more sunlight to reach the ocean. The extra heat warms both the
water and the atmosphere.
Water in the area is definitely getting warmer. In parts of the Arctic Ocean last year, surface
temperatures were 3.5° Celsius warmer than average and 1.5°C warmer than the previous record
high.
With both air and water getting warmer, the ice is melting from both above and below. In some
parts of the Beaufort Sea, north of Alaska and western Canada, ice that measured 3.3 m thick at
the beginning of the summer measured just 50 centimeters by season's end.
The new measurements suggest that melting is far more severe than scientists have seen by just
looking at ice cover from above, says Donald K. Perovich, a geophysicist at the U.S. Army Cold
Regions Research and Engineering Laboratory in Hanover, N.H.
"There's a lot less ice there than we think," he says. "And the farther we go down this path, the
harder it is to get back."
As more ice melts each summer, it takes longer for seawater to freeze each winter. Some
scientists fear that the Arctic is stuck in a warming trend from which it may never recover.—Emily
Sohn
Emily Sohn, “Artic Melt”, Science News for Kids, January 9, 2008
Accessed April 19, 2009, http://www.sciencenewsforkids.org/articles/20080109/Note2.asp
Page 7 of 8
Understanding (Information directly from the article): 3 pts
1. What is the normal pattern during a single year of the thickness or amount of
Arctic ice?
Normally, the ice thins in the summer are forms again in the winter.
2. What is happening to Arctic ice over time?
Over time the ice is disappearing.
3. What are two of the three reasons for the increased amount of melting?
The melting is caused by: strong winds blowing the ice way
Warmer water temperatures
Fewer clouds allowing more sunlight
Connections (Things we should know from class): (5 points)
1. Describe one of the two reasons why the winter season allows more ice to form.
During winter, the sun’s rays are less intense (lower angle) and the days are
shorter (less daylight)
2. What method of heat transfer is affected by cloud cover?
Cloud cover prevents solar radiation from reaching the surface.
3. Describe one of the two factors that are necessary for clouds to form.
Clouds require a lot of humidity and condensation nuclei (dust particles)
4. Why would less ice in the summer create a “warming trend”?
Ice reflects heat, so if the ice is not present, every summer will result in
increased warming. (Even more heat is absorbed by liquid water)
5. Describe one way that less Artic ice might influence weather in other parts of the
world.
Any reasonable description of : surface or deep currents, air masses, the jet
stream…
Page 8 of 8