Learning objectives
iPupils measure fast speeds, including the speed of sound.
Scientific enquiry
iiChoose measuring devices with suitable precision. (Framework YTO Sc1 9b)
iiiUse repeated readings to increase accuracy. (Framework YTO Sc1 9d)
Suggested alternative starter activities (5–10 minutes)
Recap last lesson / Share learning objectives / Problem solving / Brainstorming / Capture interest
Show a distance–time graph as an OHT.
Pupils answer some questions about the graph. /
  • Describe how to measure fast speeds.
  • Choose the most suitable measuring devices for a task. (Sc1)
  • Use repeated readings to increase reliability. (Sc1)
/ Demo to measure the speed of sound using two microphones and a millisecond timer. / Drop a £10 note or a rule between a volunteer pupil's fingers and ask him or her to catch it. Use this to introduce the idea of reaction time and its effect on the timing of short time intervals. / Show a video clip of a selection of instruments that measure time. Ask pupils to compare them and suggest which they would choose for certain uses and why. Catalyst Interactive Presentations 3
Suggested alternative main activities
Activity / Learning objectives see above / Description / Approx.
timing / Target group
C / H / E / S
Textbook K2 / i, ii and iii / Teacher-led explanation and questioning ORPupils work individually, in pairs or in small groups through the in-text questions and then on to the end-of-spread questions if time allows. / 20 min / R/G / G / R / S
Activity K2a Practical / i, ii and iii / Measuring the speed of soundMeasure the speed of sound outdoors using clapping method and/or method described in textbook. Discuss precision, reliability and accuracy. / 30 min / 
Activity K2b ICT / i and ii / How have the speeds of sound and light been measured?Pupilsuse books and/or the Internet to research the ways in which the speeds of sound and light have been measured. Could include homework, preparing a presentation, etc. / 30 min / 
Activity K2c
Catalyst Interactive Presentations3 / iii / Show animations of a car being timed over a measured distance with repeat readings being taken. / 15 min / 
Suggested alternative plenary activities (5–10 minutes)
Review learning / Sharing responses / Group feedback / Word game / Looking ahead
Working ingroups, pupils writedown five important facts aboutspeed. Each group reports back to class. List made on board which can be copied down. / Pupils discuss their responses to Activity K2b. / Group feedback on Activity K2a. / True/false/unsure quiz with pupils holding up cards. / Show a video clip of theme park rides with obvious changes in speed.
Catalyst Interactive Presentations 3
Learning outcomes
Most pupils will … / Some pupils, making less progress will … / Some pupils, making more progress will …
  • recognise that different degrees of precision are required for measuring speed in different contexts
  • learn to distinguish between precision and accuracy
  • understand that repeating measurements andtaking an average can lead to greater accuracy.
/
  • realise that very fast speeds are difficult to measure.
/
  • also justify appropriate levels of precision in measuring speed
  • relate the design of the experiment to the precision required.

Key words / Out-of-lesson learning
precision, reliable, red only: accuracy / Homework K2
Textbook K2 end-of-spread questions
Complete Activity K2b (if started in class)

© Harcourt Education Ltd 2004 Catalyst 3

This worksheet may have been altered from the original on the CD-ROM.