hour - teacher web.doc

Name: ____________________ Hour: _____ 1 What Drives the Wind? Purpose: Hypothesis: If… then … because … Materials: Styrofoam cups (calorimeters), water, sand, ring-stand, TI-Graphing Calculator, CBL unit, temperature probes, heat lamp, timer Procedure : Fill Styrofoam cups (calorimeters) with kg each of sand and water. Place calorimeters under heat lamp so each sample gets the same amount of heat (light). Program TI-Graphing Calculator and CBL unit to collect data for 40 minutes (2400 seconds). Place temperature probes into water and sand samples. Turn on heat lamp, turn on timer, start collecting data. After 20 minutes (1200 seconds) record the temperatures that the samples have reached, turn off the heat lamp, set the timer for another 20 minutes (1200 seconds) and record temperatures as the samples cool. Data: Water Temperature (° C) Sand Temperature (° C) ΔT (T 20 min–T Initial )(° C) Water Sand Initial After 20 min. (2400 seconds) ΔT (T Final –T 20 min)(° C) Final Specific Heat: C J/kg- °C 4180 1381 Mass = kg Analysis: 1. Calculate the change in temperature ΔT using the equation in the data table. Enter this value in the data table. 2. Calculate the amount of heat that each sample absorbed, in heating up: Q water =m water C water ΔT (T 20 min–T Initial ) water = ?