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Rogue Physicist.  Free resources for physics education © 2006-2016 Dorian Pascoe.  Email: dorian.pascoe@hotmail.co.uk

Most resources are available under a Creative Commons Licence.  Visit our mirror at www.physicsweb.altervista.org

 

 

 

 

Simple Pendulums

 

 

 

 

 

Objectives:

 

  
 

 

 

Tick tock! Tick tock!

  

 

 

• Know that pendulums can be used as simple timing devices.

 

 

• To complete an APP task, looking at the range and interval of data from some practical work.

 

 

• Be able to investigate the factors affecting the period of a pendulum.

 

 

  

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Task 1 - Starter

 

  
 

 

 

What's the time?

 

 

  

 

Old clocks often have a pendulum, which swings from side to side to keep time.

 

 

 

• What type of energy does the pendulum gain as it moves upwards towards the top of its path?

 

 

• What type of energy does it gain as it swings downwards towards the lowest point of its path?

 

 

  

 

 

 

 

 

 

 

 

Swing, little pendulum!

  

 

An old clock.

  

 

 

 

 

 

 

 

 

 

 

Task 2 - Looking at pendulums

 

  
 

 

 

I can do science!

  

 

This is the Pendulum lab.  It allows you to investigate the factors affecting the time period of a pendulum.

 

 

 

What happens to the size of the swing after a while?

 

 

Does the size of the swing affect the time period?

 

 

Explain your answers using ideas about friction, speed and energy.

 

 

  

 

 

 

 

 

 

 

The pendulum lab!

 

 

 

 

 

 

 

 

 

 

 

 

Task 3 - Assessing Pupil Progress (APP) task

 

  
 

 

 

Think hard!

 

 

  

 

Your teacher will give you a copy of the APP task, below.  Complete the task individually. 

 

 

 

 

 

When you have finished, write your name on your work and hand it to your teacher.

 

 

Thanks to Rocket Resources for this task.  Click here, or on the image above, to download a copy as a word document.

 

  

 

 

 

 

 

 

 

 

 

 

Task 4 - Using a pendulum to tell the time

 

  
 

 

 

What's the time, Mr Wolf?

 

  

 

Your teacher will give you some string and a small piece of plasticine.  See if you can make a pendulum with a time period of one second.

 

 

 

What factors affect the time period of the pendulum?

 

 

How long can your pendulum be used as a timer, before the oscillation (swing) is too small to see?

 

 

 

 

Extension:  Did the mass of the bob affect the time period of the pendulum?  Explain your answer, using scientific ideas about energy.

  

 

 

 

 

 

 

 

 

 

 

 

 

 

Task 5 - Wave pendulum

 

  
 

 

My brain electrodes hurt.

 

  

 

This is a Wave pendulum.  It is made from lots of individual pendulums, each with a slightly different period.

 

 

 

 

 

 

 

 

Your teacher will show you a wave pendulum working.  Watch the patterns formed over the course of a minute!

 

 

  

 

 

 

 

 

 

Video - wave pendulum

 

  
   

 

 

This video shows a wave pendulum.

 

  

 

 

 

 

 

 

Video - giant wave pendulum

 

  
   

 

 

This video shows a GIANT wave pendulum.

 

  

 

 

 

 

 

 

 

 

 

 

 

 

Task 6 - Newton's cradle

 

  
 

 

 

A Newton's cradle.

Danger: hypnotic...

  

 

This is a Newton's Cradle.  It is similar to a pendulum in some ways, but can also show us some interesting things about momentum.

 

 

 

Click, clack!

 

 

 

• What happens when you swing a single steel ball?

 

 

• What happens when you swing two steel balls together?

 

  

 

 

 

 

 

 

Video - Newton's cradle tricks

 

  
   

 

 

This video shows some of the things a Newton's cradle can do.