yes it is. just don't be too aggressive with it. don't down shift too soon as to over-rev the engine. This also saves on the brakes and will not harm your drive train in any way as long as it's done correctly. Be careful though.if you downshift into to low of a gear too soon it could cause the back tire to skid and maybe make you lose control.one gear at at time.just like up shifting.
Yes, you should always match your engine speed to road speed by downshifting as you slow. It saves wear on the brakes as you slow, helps you slow faster and puts you in the right gear in case you have a need to accelerate again. ALL riders should do so. Most motorcycles have wet clutches so they don't wear as fast as car clutches.
Depends how course your salt and sand is, but I'm assuming salt is table salt consistency, and sand has typical particle size of about 1 mm or so. If so, use a sieve which has openings of 1 -2 mm (maybe 8 - 16 mesh?) and sieve everything through it. The sesame seeds should remain in the sieve, while the iron filings, sand and salt mixture passes through. Then use a magnet to remove iron filings. Finally, dissolve the salt/sand mix up in water, and filter off the sand.
Run it through a strainer onto a paper plate, run a magnet over it and get the iron filings. Then take the mixture on the plate and put in water, the salt should dissolve into the water. From there, find a peice of cloth preferably something like a T-shirt (A towel might be to thick). Run your sand/salt/water mixture through the T-Shirt and let the water poor out the otherside letting the T-shirt catch the sand. Have the water poor out into another container. Then take the salt water and boil it till thiers nothing left and the salt should be sitting at the bottom of the pan (It'll be pretty hot). Now you have the Copper, and Rice. This part I wasnt sure of but what MIGHT work is putting the mixture of copper and rice on a plate and runnign a comb through it dragging the rice to another side of plate. And thats that. Hope I helped.
1 Pass through a coarse sieve (coarse enough to let the sand through; but not coarse enough to let the rice through). 2 Pass it over a sheet, under which there is a strong magnet. The magnet will hold back the iron filings. 3 Dissolve in water. The salt will dissolve, leaving the sand and copper carbonate. The water can be evaporated to recover the salt. 4 Dry the sand and copper carbonate, then place it in an organic solvent such as ethanoic acid. This will dissolve the copper carbonate, leaving behind the sand 5 evaporate the ethanoic acid to recover the copper carbonate. Solubility tables are useful for working out things like this. Edit: Thinking about it, if this is a science question, then simply sieving out the rice may not be the answer (there could always be some coarse sand particles present) In this case, it is better to leave the rice/sand separation til last; then place the mix in salty water (as much salt as you can dissolve in hot water). Saturated salt solution specific gravity is about 1.2, and for rice about 1.1, so the rice will float off.
