TTEC ONLINE LEARNING 2020

Timaru Technology Education Centre

Structures, Mechanisms, Materials & Design Technology

Mr Mills & Mr McNamara Weeks 3-4

The Challenge (Design Brief) How?

We are going to Investigate

simple machines, specifically levers.

This online task is a

little bit different from

previous ones we have

completed as most of

the learning will take

place by investigating

online and hopefully

some prior knowledge.

During the Level 4 lockdown initiated by NZ Government, staff at TTEC are keen for our students to continue with their Technology learning even though they are at home.

The plan is to provide you with activities and challenges you can engage with in the comfort of your own home, that will be challenging, stimulating and fun.

We look forward to teaching you all once again, when this is all over.

Take care, be safe, be kind, be tolerant and follow guides set by the Government and all will be well.

See you at TTEC soon hopefully.

TTEC Staff

Let’s get started...

Did you know that there are six basic machines which are split into two families?

The two families are the lever family and the inclined plane family.

Can you match up the machines which are lettered, with the machine images numbered, and then split them into their two families?

You can ask you “bubble companions” to help.

Note...

Remember, with any of the TTEC online tasks, we do

not know if you have access to printers etc. So with any

written work, copy the tables, tasks etc. and record

onto paper/school notebook or Google Docs, MS Word

etc. if you have access to them.

You can also take a digital photo/video of what you do

and send them to us.

Email addresses are on the last page.

Not a lot of people know this….

Gears are wheels with teeth that can either increase the speed of a machine or its force, but not both at the same time. Although it's

not immediately obvious just by looking at them, gears actually work in exactly the same way as levers (just as wheels do). To make it

even more confusing a gear is also a wheel and axle that has teeth along the wheel. Often they are used in combination with one

another and change the direction of forces. Not a lot of people know that...now you do. We will cover Gears in the next online lesson.

Machines Number

A Lever

B Screw

C Inclined plane

D Pulley

E Wedge

F Wheel & Axle

Families Machine A-F

1 Lever Family

2 Inclined Plan Family

1 2 3

4 5 6

How did you do? Don’t worry we will find out all the answers as we go along

via the online learning tasks from week to week.

TTEC ONLINE LEARNING 2020

Timaru Technology Education Centre Investigating Simple Machines

Levers

_______ _______ _______ _______ ________ ______

_______ _______ _______

___ Class Lever ___ Class Lever ___ Class Lever

We are going to focus on Levers for this first investigation into Simple Machines. I would like you to watch the following video (it is about 12 minutes long). This video is very good but uses the old imperial system of measurement (ask your parents/caregivers/

grandparents) and we use the metric system. With that in mind when you hear him say pounds convert to kilogrammes, when he says feet convert to metres. The theory is the same but in USA they are one of the few countries still using the imperial system.

Ok get yourself a glass of water, relax and watch this video...twice if you can would be great.

https://www.youtube.com/watch?v=OdM2jWg2uEE

These ones are also ok for a quick recap

https://www.youtube.com/watch?v=E8RA9Kw_IaE

https://www.youtube.com/watch?v=lueqE0lxLyc

That first video has lots of great examples and very clear explanations

of just exactly what a lever is and what it can do.

Let’s see what you can remember?

Can you Label the levers below with either:

1) 1st class, 2nd class or 3rd class lever?

2) Label where the Loads are acting?

3) Label where the Effort/Force is acting?

4) Label where the Pivot/Fulcrum is?

Refer to videos if you need to

Without getting up from your seat look around you. Can you see anything that may be a lever?

Name 3 please. 1) _________________________ 2) ________________________ 3) ___________________________

Can you think of any instances of where you have used a lever?

Name 3 please. 1) _________________________ 2) ________________________ 3) ___________________________

Optional Task

The next video link below has a good explanation of the Math involved in calculating Forces and Distances in the 3 classes of levers.

This requires a bit of concentration but is worth it to gain an understanding of the Physics/Math involved.

If you take a path in Engineering etc. You will need to know this.

https://www.youtube.com/watch?v=oJGcMbzwak8

We will cover the Math content at TTEC rather than doing it here online, but as I said watch it if you feel inclined (no pun intended).

TTEC ONLINE LEARNING 2020

Timaru Technology Education Centre Investigating Simple Machines

What do 1st, 2nd and 3rd Class Levers do, and what are the differences?

A lever is a simple machine. It is something that can be used in a lot of ways. One way is by measuring things, or by seeing which weighs more (can you think of any examples?). A lever is supported by a fulcrum which it uses to lifts weights. It is one of six simple machines.

As we now know there are three types of levers: first-class, second-class and third-class.

The earliest remaining writings about levers are from the 3rd century BC. They were written by Archimedes. "Give me a place to stand, and I shall move the earth." is a famous quote from Archimedes who stated the correct mathematical principle of levers

(quoted by Pappus of Alexandria).

The difference between the three classes of levers is where the fulcrum is located and where the forces are.

First class

A first-class lever is a lever where the fulcrum is in between the effort and resistance (the load).

Seesaws and crowbars are examples of first class levers.

1st difference -The fulcrum is in the middle unlike the other 2 classes of lever.

2nd difference -The direction of the effort force is opposite to the resistance force.

Second class

A second-class lever is where the resistance is between the effort and the fulcrum.

Wheel barrows and wrenches are examples of second class levers.

1st difference –The fulcrum is on the end.

2nd difference –The direction of resistance (load) movement and the direction of the effort force movement are the same.

3rd difference –The resistance (load) is between the effort force and the fulcrum.

Third class

A third class lever is where the effort is between the resistance and the fulcrum.

Staplers and your forearm are examples of third class levers.

1st difference –The fulcrum is on the end.

2nd difference –The direction of resistance (load) movement and the direction of the effort force movement are the same

3rd difference - The effort force is between the fulcrum and the resistance force (load).

I have included a few ways above to define the specifics of each lever as hopefully one will suit your need.

YOU MAY OR MAY NOT HAVE NOTICED THAT ON EACH PAGE THERE HAS BEEN A MINION ON A BIKE.

There are three simple machines found on a bicycle: the lever, the pulley, and the wheel-and-axle.

Can you identify where they are on your bike if you have one?

TTEC ONLINE LEARNING 2020

Hopefully now you have a better understanding about the three classes of levers.

You will cover this again once you return to TTEC via interactive activities with Lego Dacta.

Can you label the following images below to indicate if they are either 1st, 2nd or 3rd class levers?

Refer to the image on the left for reference...if you need to.

Timaru Technology Education Centre Investigating Simple Machines

Levers

Teacher contact and images

tmills@ttec.school.nz patrickm@ttec.school.nz

Please feel free to email with

any questions regarding projects.

Conundrums For The Day

What goes through a door but never goes in or out?

What has a hundred limbs but can’t walk?

What has four fingers and a thumb but is not a hand?

Funny Video For The Day

https://www.youtube.com/watch?v=AfWsM4PKPio

https://www.youtube.com/watch?v=2wQUW7Jsxs0