[_ Old Earth _] basic machines

[jasoncran]

i assist at times with royal rangers and i demonstrate science or things of that nature. i want to demonstrate simple machines

are these?

the lever, the wheel, and gears and i missing a few others, help?

i also intend to teach the lever tommorow and will use a floor jack to do that with and go into pry bars.

 

[bigllama]

inclined plane, pulley

 

[jasoncran]

ah i forgot, pulley, hmm i dont think i can do a demo on that at church as theres no trees nearby. a video or crane would have to do and where i work i have a crane or two that we use and inclaned plane. refresh my memory.

 

[jasoncran]

never mind thats a ramp. i can get one of those. or take a simple ply wood or 2 x 6 and use my truck for that.

 

[Roof]

Wedge

 

[Rhea]

Don't forget the basic machines even more basic woven into our lives.

Levers - almost all basic machines are a form of the lever:
Doors, lightswitches, screws, bottle openers,window locks, gas pedal in the car, handicap ramps, plows, zippers, etc. Gears are really a series of levers.

here's the contents of section one "The Mechanics of Movement" of McCaulay's book The Way Things Work my very favorite engineering book for lay people.

Inclined plane, levers, wheel and axle, gears and belts, cams and cranks, pulleys, screws, rotating wheels, springs, friction.

 

[Rhea]

ah i forgot, pulley, hmm i dont think i can do a demo on that at church as theres no trees nearby. a video or crane would have to do and where i work i have a crane or two that we use and inclaned plane. refresh my memory.

You can buy 1" diameter pulleys at the hardware store and use a rope to show that more pulleys will increase rope needed, but decrease work to lift the same weight. You can use something light (like an unopened gallon of paint) that can be suspended from a rolling coat rack. Three pulleys at top, two at bottom attached to handle of can, e.g.

 

[jasoncran]

i was going to point out the levers on my truck and in all cars with hydraulic brakes. the simple brake pedal and explain mechanical advantage and next week take a flex plate and or starter that work but are removed and then show them again in action my truck and explain what gear reduction is and also explain what torque is.

yes i realise all that is easily found.

cars are the esieast way i can explain them.

i took a fan and took compresed air to it and show them that magnets can be used to make power and the whole idea of windmills is based on that. one boy recognised what i did

 

[jasoncran]

You can buy 1" diameter pulleys at the hardware store and use a rope to show that more pulleys will increase rope needed, but decrease work to lift the same weight. You can use something light (like an unopened gallon of paint) that can be suspended from a rolling coat rack. Three pulleys at top, two at bottom attached to handle of can, e.g.

thanks where i work we dont have multiple pulleys and besides that is something i should have at my house any way.

 

[jasoncran]

ah i looked ramps.

a wheel barrel has both a wheel and a lever of sorts as when one dumps the thing you are carrying as the wheel barrel has a leverage effect as the tire is the fulcrum and gives you a mechanical advantage.

i have to keep this basic and not go into way above the youngest and yet all do learn something.

 

[theLords]

Aw, the royal rangers :heart Our troops where into crazy things (the older kids) flying potatoes and what not.

Have fun Jason!

 

[jasoncran]

Aw, the royal rangers :heart Our troops where into crazy things (the older kids) flying potatoes and what not.

Have fun Jason!

lol. so your church has that group? i thought it was only a church of god thing.

and the brother leads it has had the kids lauch rockets(chemical type) and also done the soap box derby and a last week it was kites, though only two kids did the kite thing and nathan was one of them. i havent flown a kit since i was nathans age.

 

[Barbarian]

Rig up two broomsticks and ropes like this. Start with one kid holding each broomstick and one kid pulling on the rope. Watch what happens. Then add two more holding the broomsticks and try again. The pulley lets the kid with the rope pull with more force than several other kids.

Show that the force is multiplied by the number of loops, but the kid pulling the rope has to pull a longer length of rope to exert that greater force. Force is reduced, but the work remains the same, since work is equal to force times distance. The pulleys reduce the force needed, but increase the distance.

The mechanical advantage is the number of pulleys.

An inclined plane works the same way. Pushing a load up a ramp instead of lifting it reduces the force but not the work. The mechanical advantage of the ramp is the length of the ramp divided by the height of the ramp. Again, you can show that force is reduced but work remains the same, because work is force times distance.

If it takes ten newtons to raise a load one meter, then rolling it up a ten meter ramp will only require one Newton.

10N X 1 meter = 1N X 10 meters.

 

[jasoncran]

can you send me that in some form a pic? so that i can work that one . they love demonstrations.

 

[Barbarian]

http://www.qldscienceteachers.com/junior-science/physics/experiments/simple-machines

http://www.experiland.com/html_proj... your friends with a simple pulley system.htm

 

[jasoncran]

ok thats what i figured after i gave it some thought. lol one big shoe lace!

 

[jasoncran]

it worked. i had the smallest kid overpower the strongests with that . you have to pull from the side. and it worked great.i will do an inclined plane and also gears.

then onto organges and other citrus being batteries. now then i want to connect them into seriesl to build up enough voltage. how much power can i get out of three oranges or other citrus. i want to light up a light but i need to know how much i can get.