DP Physics (last assessment 2024)

Test builder »

Question 19M.3.HL.TZ2.13c

Select a Test
Date May 2019 Marks available [Maximum mark: 2] Reference code 19M.3.HL.TZ2.13c
Level HL Paper 3 Time zone TZ2
Command term Calculate Question number c Adapted from N/A
c.
[Maximum mark: 2]
19M.3.HL.TZ2.13c

A solid sphere is released from rest below the surface of a fluid and begins to fall.

(c)

The weight of the sphere is 6.16 mN and the radius is 5.00 × 10-3 m. For a fluid of density 8.50 × 102 kg m-3, the terminal speed is found to be 0.280 m s-1. Calculate the viscosity of the fluid.

[2]

Markscheme

any evidence (numerical or algebraic) of a realisation that

6 π η r v + ρ g V = W  ✔

« η = 6.16 × 10 − 3 − 4.366 × 10 − 3 6 π × 0.005 × 0.280 »

η = 0.0680 «Pas»✔

 

Examiners report

When the condition for forces in equilibrium was correctly formed, many candidates managed to obtain the correct answer. The working was often poorly presented making it difficult to mark or award marks for the process.

Syllabus sections