Measure the mass of the block and wrap it with an insulating material to reduce the energy transferred to the surroundings. Insert the thermometer into the heater
Measure the initial temperature of the block and set the p.d. to 10. Turn on the power supply and start a stopwatch
The current in the circuit does work on the heater and transfers energy electrically from the power supply to the heater's thermal energy store. This energy is transferred to the material's thermal energy store by heating, causing the material's temp. to increase
As the block heats up, take readings from the thermometer and current every 10 minutes- the current should not change
When many readings are collected, turn the power supply off. Use P=IV and E=Pt to calculate how much energy is transferred to the heater
A graph can be plotted wit thermal energy against temperature
Different materials can be used and compared
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The effectiveness of Materials as Thermal Insulato
Boil water in a kettle and pour some into a beaker with a lid. Measure the mass of the water
Use a thermometer to measure the initial temperature
Seal the container and leave it for 5 minutes
Remove the lid and measure the final temperature
Repeat the experiment but wrap the container with a material each time after sealing. Alternate it everytime.
The lower the temperature difference, the better the insulator
Thickness also could be investigated by adding different layers of the same material- thicker the better
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Finding a component's I-V characteristics
Set up a test circuit
Begin to vary the variable resistor. This alters the current flowing through circuit and changes the p.d as well
Take several pairs of readings from the ammeter and voltmeter- repeat each reading twice
Swap over the wires connected to the cell so the direction is reversed
Plot a graph with current vs voltage for the component
Resistance is calculated by V=IR
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Investigating Resistance in Series
Build a circuit using one of four identical resistors. Make a note of the p.d of the battery
Measure the current on the ammeter. And use V=IR to find the resistance
Add another resistor in series.
Measure the current and p.d. to calculate the resistance
Repeat steps 4 and 5 until four resistors are added
Plot a graph of the number of resistors against the total resistance
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Investigating Resistance in Parallel
Build a circuit using one of four identical resistors. Make a note of the p.d of the battery
Measure the current on the ammeter. And use V=IR to find the resistance
Add another resistor in parallel.
Measure the current and p.d. to calculate the resistance
Repeat steps 3 and 4 until four resistors are added
Plot a graph of the number of resistors against the total resistance
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Measuring Density of a solid object
Use a balance to measure its mass
If it is a regular solid, start by measuring its length, width and height using a ruler and calculate its volume
For an irregular solid, submerge the object in a eureka can filled with water with a measuring cylinder under its beak. The water displaced is equivalent to the volume of the object
Substitute into the formula m=ρv
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Measuring Density of a liquid
Place a measuring cylinder on a balance and zero the balance
Pour 10 ml of the liquid into a measuring cylinder and record the mass
Pour another 10 ml and repeat the process until the cylinder is full and recording the total mass and volume each time
For each measurement, use the formula to find the density (1 ml=1 cm3)
Finally, take an average of the calculated densities
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