User interface language: English | Español

Date November 2019 Marks available 2 Reference code 19N.2.SL.TZ0.1
Level Standard level Paper Paper 2 Time zone 0 - no time zone
Command term Calculate Question number 1 Adapted from N/A

Question

The graph shows the variation with time t of the horizontal force F exerted on a tennis ball by a racket.

The tennis ball was stationary at the instant when it was hit. The mass of the tennis ball is 5.8 × 10–2 kg. The area under the curve is 0.84 N s.

Calculate the speed of the ball as it leaves the racket.

[2]
a.

Show that the average force exerted on the ball by the racket is about 50 N.

[2]
b.

Determine, with reference to the work done by the average force, the horizontal distance travelled by the ball while it was in contact with the racket.

[3]
c.

Draw a graph to show the variation with t of the horizontal speed v of the ball while it was in contact with the racket. Numbers are not required on the axes.

[2]
d.

Markscheme

links 0.84 to Δp

v=«0.845.8×10-2=» 14.5 «m s–1»✔

NOTE: Award [2] for bald correct answer

a.

use of Δt = «(28 – 12) × 10–3 =» 16 × 10–3 «s» 

F¯ =«pt=» 0.8416×10-3 OR  53 «N» ✔

NOTE: Accept a time interval from 14 to 16 ms
Allow ECF from incorrect time interval

b.

Ek = 12 × 5.8 × 10–2 × 14.5

EkW

s = «WF=12×5.8×10-2×14.5253=» 0.12 « m » ✔

 

Allow ECF from (a) and (b)

Allow ECF from MP1

Award [2] max for a calculation without reference to work done, eg: average velocity × time

c.

graph must show increasing speed from an initial of zero all the time ✔
overall correct curvature ✔

d.

Examiners report

[N/A]
a.
[N/A]
b.
[N/A]
c.
[N/A]
d.

Syllabus sections

Core » Topic 2: Mechanics » 2.4 – Momentum and impulse
Show 69 related questions
Core » Topic 2: Mechanics
Core

View options