DP Physics (last assessment 2024)

Question 17N.3.HL.TZ0.11a.ii

Date	November 2017	Marks available	[Maximum mark: 2]	Reference code	17N.3.HL.TZ0.11a.ii
Level	HL	Paper	3	Time zone	TZ0
Command term	Calculate	Question number	a.ii	Adapted from	N/A

a.ii.

[Maximum mark: 2]

17N.3.HL.TZ0.11a.ii

The diagram shows a simplified model of a Galilean thermometer. The thermometer consists of a sealed glass cylinder that contains ethanol, together with glass spheres. The spheres are filled with different volumes of coloured water. The mass of the glass can be neglected as well as any expansion of the glass through the temperature range experienced. Spheres have tags to identify the temperature. The mass of the tags can be neglected in all calculations.

Each sphere has a radius of 3.0 cm and the spheres, due to the different volumes of water in them, are of varying densities. As the temperature of the ethanol changes the individual spheres rise or fall, depending on their densities, compared with that of the ethanol.

The graph shows the variation with temperature of the density of ethanol.

(a.ii)

When the ethanol is at a temperature of 25 °C, the 25 °C sphere is just at equilibrium. This sphere contains water of density 1080 kg m^–3. Calculate the percentage of the sphere volume filled by water.

[2]

Markscheme

$\frac{{0.87}}{{\frac{4}{3}\pi {{\left( {0.03} \right)}^3} \times 1080 \times 9.8}}$

$\frac{{0.87}}{{1080 \times 1.13 \times {{10}^{ - 4}}}}$

$\frac{{785}}{{1080}}$

0.727 or 73%

Allow ECF from (a)(i)

Syllabus sections

Option B: Engineering physics

Option B: Engineering physics » Option B: Engineering physics (Additional higher level option topics) » B.3 – Fluids and fluid dynamics (HL only)

Option B: Engineering physics » Option B: Engineering physics (Additional higher level option topics)

Question 17N.3.HL.TZ0.11a.ii

Select a Test

Syllabus sections

Confirm action