2 VariablesManipulated Variable- Different types of metals (aluminum, iron, zinc, brass)Responding Variable- Rate of hear conductionControlled Variable- Same diameter (1in.)Controlled Variable- Same length (1ft.)
3 QuestionHow does different types of metals (aluminum, iron, zinc, brass) affect the conduction of heat?
4 HypothesisAs I increase the temperature of different metals (aluminum, iron, zinc) by heating them with a candle flame, then the aluminum will have a faster heating rate because aluminum is a more lighter metal than iron & zinc, which heat can travel fast.
5 Materials Ruler Metal rod (iron, zinc, aluminum, brass) Permanent markerLighterCandle6-10 metal thumbtacksOven mittStopwatchNote: rod has to be at least 1ft long same diameter
6 ProcedureUsing ruler, measure and mark 1 inch intervals on the aluminum rod with a permanent marker.Light the candle. Drip a little bit of wax on the head of the metal thumbtack. Attach the thumbtack to one of the marks on the aluminum rod and attach the rest of the thumbtacks along the rest of the marks.Let the wax cool for about 10 minutes.Using your oven mitts, hold one end of the aluminum rod in the candle flame near the first tack.Use the stopwatch to time how long it takes for all the thumbtacks to fall off. Start the stopwatch when first tack falls.To record the rate the heat moved along the rod, you can divide the number of inches (number of tacks minus 1) by the time it took all the tacks to fall off.Let the aluminum rod cool completely and repeat steps 2-6 two more times.Repeat steps 1-7 using the iron, brass, zinc and aluminum rods.Safety- Do not touch flame, wear oven mitts during experiment to protect hands from burn and have adult supervision.