How do you incerase inertia with 15 metal washers that you have to put into metal can so it can roll down ramp

Question

we can add almost anything to inside of metal can to hold washers, but the objective is to make it roll as fast as possible down ramp.... HELP!

oh, it's a campbells 10.5 oz soup can and it has to be able to roll down straight or else it's no good.

Answer 1

To go faster down the ramp you want to decrease inertia.

Best would be to make a column with the washers and glue them in the center of the can. By being close to the center - you reduce inertia.

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When intertia is low - the can will be a bit faster.

Putting them along the edge - increases inertia - and will cause the can to roll further once it leaves the ramp. But the can will roll down the ramp a bit slower because it needs to build up the inertia.

Answer 2

You want something dense and heavy like lead fishing weights that you can probably get at Wal Mart, Kmart or a Super Target.

I am assuming that your metal cart is not rolling on the washers like a car. You could add four screws to the cart and put the washers, loosely, on the inside of screws and thus create a tiny car.

But, if you are running the metal car as a sledge so that it slides down the ramp then you want something that is dense and low to provide the most downward force without providing any tipping over force. The tipping over force would push down on the cart digging it into the ramp and so slowing it down. Your goal is to get your cart going fast so you want to put as much mass as close to the bottom of the cart as possible. You may want to attach those lead weights to the rear of the cart so they actually tip the cart up a little thus letting it overcome the resistance of the ramp better.

Surfers on surfboards start near the middle/rear of the board, only when they are going fast and well do they try stunts like hanging ten where you step to the front of the board and grab it only with your toes. If they do that then they are providing too much down force and it is easy to force the board under the water. If they stay in the middle/rear of the board then they keep the bow of the surf board above the waterline and thus provide less resistance to travel. You want to take a page from their book and put your weights near the middle/rear of the cart to reduce the amount of friction and get the most benefit out of your inertia.

If you mean by straight that your soup can is standing up with the label where you can read it then you have a flat surface and you want to put the weight near the middle/rear; say a point just rearward of the middle to make the soup can slide down the ramp easier. You would also want to find the front of the can and file it down a little to smooth it and give it less resistance. That may be cheating to some people, but the idea of the experiment is to use the laws of physics to make your soup can slide faster and if your soup can has less friction at the front it will slide faster.

Now if the only thing you can put inside of the can is washers and whatever is attaching them then use magnets to make them stick to the bottom of the can, provided it is as steel can of course. Other wise use a lot of glue. Of course I would drill a hole in the bottom of the can and put a screw up into the can and stack the washers on the screw. Or better yet I would put in a few shorter screws to hold those washers. If you use a wood screw the head would be flat and it wouldn’t interfere with the sliding action of the can, but if you used round headed metal screws then you could use those screws as fixed wheels to make your can go even faster. Again a little filing to make the screw head smooth would be a good idea.

Another method to use would be to grease the track or the bottom of the can, or to oil it; but your teacher would probably rule such “creative thought” as cheating.

Answer 3

Distribute them evenly say 3 rows (top middle bottom) with five in each, depending on washer size and can size. Need to be close to the outer surface

Answer 4

glue them in circles in the top, middle and bottom diameter inside can