Casio EA-200 - Manual (Page 42)

20020601
English
Activity: Setup Activity: Setup
2-15-1
í Equipment
500ml Clear Plastic Bottles (3) Dry Earth (or Sand) Seawater (or Water)
Styrofoam Boards Rain Cover
Temperature Measurement Setup (EA-200, graphic scientific calculator, data communication
cable, temperature probe (3))
í Preparing the Plastic Bottle
u Remove the label from the plastic bottle, wash it out, and let it dry.
u Pierce the center of each of the Styrofoam boards with a temperature probe, attach the
board/probe assembly to a bottle cap, and then seal the bottle.
í Setting Up
u Weigh the empty bottle and the other two bottles to determine the mass of the substance
inside each.
u Locate the bottles in an area that is constantly
exposed to sunlight.
The difference in the specific heat of landmasses and seawater causes differences between
the climate of coastal areas and inland areas, even when they are located at the same
latitude.
This simple activity investigates these differences.
Specific heat expresses how the temperature of a unit mass of a substance changes when
a quantity of heat is applied. The greater the specific heat of a substance is, the smaller is
its change in temperature. The expression for this change in temperature is shown below.
The table shows the specific heat values for a number of common substances.
ͬT =
ͬ T ( °C) : Change in Temperature of Substance
ͬ Q (J) : Heat Quantity Applied to Substance
m (g) : Mass of Substance
c (J/g °C) : Specific Heat of Substance
T ( °C) : Measured Temperature
The above indicates that seawater is difficult both to heat and cool, while landmasses are
easy to heat and cool. The result is that there tends to be less fluctuation between heat and
cold in marine climates, and greater fluctuation further inland. It should be noted, however,
that there are many different variations in actual climates, due to ocean currents, air
currents, topography, wind patterns, and other factors. This activity investigates changes in
the temperature of common everyday substances as they absorb heat from sunlight. It also
compares the tendency to change temperature with measured values.
Topographic Conditions and Climate
Theory
1 Styrofoam Board
2 Air
3 Seawater
4 Earth
5 Temperature Probe
6 Rain Cover
7 EA-200
1 Plastic Bottle
2 Bottle Cap
3 Styrofoam Board 5cm × 5cm × 1cm
4 Temperature Probe
5 Hole Diameter: 6mm
Substance c (J/g °C) T ( °C)
Water 4.2 15
Ice 2.1 0
Seawater 3.9 20
Rock 0.8 20
Wood 1.2 20
ͬQ
mc