Thermal Insulation
Q1.
A student investigated the properties of three types of insulation.
Figure 1 shows the apparatus the student used.
Figure 1

In the investigation different insulating materials were placed in contact with the hot metal plate.
Temperature probes measured the temperature on each side of the material.
The temperature probes were connected to a data logger.
Figure 2 shows how the temperature measured by temperature probe 2 changed over 10 minutes for each of the materials.
Figure 2

(a)     What was the temperature of the hot metal plate?
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(1)
(b)     Which material is the best insulator?
Tick one box.
 
A		B		C		
Give the reason for your answer.
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(2)
(c)     Another student repeated the investigation but doubled the thickness for all three insulating materials.
Suggest how using thicker insulation would affect the results of the second student's investigation compared with the first student's results.
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(2)
(d)     The students could have used a thermometer instead of temperature probes and a datalogger.
Figure 3 shows the datalogger screen and a thermometer.
Figure 3

Give two advantages of using the datalogger and temperature probes compared to a thermometer.
1. _________________________________________________________________
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2. _________________________________________________________________
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(2)
(e)     The table gives information about four types of insulation that could be used for insulating the cavity walls of houses.
 
Type of insulation	Thermal conductivity in W/m °C	
Felt wool	0.070	
Mineral wool	0.040	
Polyurethane foam	0.030	
Rock wool	0.045	
Explain which one of the types of insulation in the table would be the best to use for cavity wall insulation.
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(2)
(Total 9 marks)