2.3.4 Consequences of thermal energy transfer

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Question 4

A student investigates how the exposed surface area of a hot brass cylinder affects the rate at which it cools.

Two different insulating sleeves are used:

Sleeve A covers part of the cylinder, leaving $60%60\%$ of its curved surface area exposed to the air.
Sleeve B covers more of the cylinder, leaving only $30%30\%$ of its curved surface area exposed.

The temperature of the cylinder is measured at $t = 0$ and then every $s20\text{ s}$ up to $s120\text{ s}$ . The student's results are recorded in Table 1.1:

	Cylinder with Sleeve A	Cylinder with Sleeve B
$t /$ ...	$θ/\theta /$ ...	$θ/\theta /$ ...
$0$	$85.0$	$85.0$
	$79.5$	$82.0$
	$74.5$	$79.5$
	$70.0$	$77.0$
	$66.0$	$75.0$
	$62.5$	$73.0$
	$59.5$	$71.5$

Complete the headings and the time $t$ column in Table 1.1.

[2]

Write a conclusion to this experiment, stating for which sleeve the cooling rate is greater. Explain your answer with reference to the temperature values in Table 1.1.

[2]

Suggest a change to the apparatus or setup that could produce a greater difference between the cooling rates of the cylinder with Sleeve A and Sleeve B. Explain why this change would produce a greater difference.

[2]

A student thinks that the cooling rate is directly proportional to the percentage of the surface area uncovered. To investigate this, they plan to plot a graph of cooling rate against the percentage of uncovered area.

Describe how the graph line will show whether the cooling rate and the percentage of uncovered area are directly proportional.

[2]

Suggest one factor, other than the surrounding room temperature, that should be kept constant in repeats of this experiment to ensure a fair comparison.

[1]

2.3.4 Consequences of thermal energy transfer

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Question 4

A student investigates how the exposed surface area of a hot brass cylinder affects the rate at which it cools.

Two different insulating sleeves are used:

Sleeve A covers part of the cylinder, leaving $60%60\%$ of its curved surface area exposed to the air.
Sleeve B covers more of the cylinder, leaving only $30%30\%$ of its curved surface area exposed.

The temperature of the cylinder is measured at $t = 0$ and then every $s20\text{ s}$ up to $s120\text{ s}$ . The student's results are recorded in Table 1.1:

	Cylinder with Sleeve A	Cylinder with Sleeve B
$t /$ ...	$θ/\theta /$ ...	$θ/\theta /$ ...
$0$	$85.0$	$85.0$
	$79.5$	$82.0$
	$74.5$	$79.5$
	$70.0$	$77.0$
	$66.0$	$75.0$
	$62.5$	$73.0$
	$59.5$	$71.5$

Complete the headings and the time $t$ column in Table 1.1.

[2]

Write a conclusion to this experiment, stating for which sleeve the cooling rate is greater. Explain your answer with reference to the temperature values in Table 1.1.

[2]

Describe how the graph line will show whether the cooling rate and the percentage of uncovered area are directly proportional.

[2]

Suggest one factor, other than the surrounding room temperature, that should be kept constant in repeats of this experiment to ensure a fair comparison.

[1]

2.3.4 Consequences of thermal energy transfer

Question 4

Markscheme

2.3.4 Consequences of thermal energy transfer

Question 4

Markscheme

2.3.4 Consequences of thermal energy transfer

Question 4

2.3.4 Consequences of thermal energy transfer Questions

2.3.4 Consequences of thermal energy transfer

Question 4

2.3.4 Consequences of thermal energy transfer Questions