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Key conceptsPhysicsFrictionMotionMaterialsIntroductionHave you ever tried to acquire a running start and slide throughout a smooth, wooden floor while wearing socks? What happens if you attempt the same thing on a carpeted floor or while wearing shoes? The amount of friction in between your feet and the floor surchallenge determines just how well you deserve to slide. Some combinations of surencounters, such as socks on a wooden floor, develop extremely little bit friction. Other combinations, such as rubber soles on a wood floor, create much more friction. In this project you"ll carry out a a lot smaller-scale friction experiment by launching tiny objects along a surconfront through a rubber band also. How perform you think friction will influence how much the objects slide?BackgroundFriction is the force that opposes motion in between two surfaces that are touching one another. Friction is a really essential part of everyday life—without it, you wouldn"t have the ability to walk because your feet would certainly just slip on the floor! Sometimes it is very necessary for surdeals with to have high friction, such as the rubber tires of a vehicle on the road. Other times we desire surdeals with to have low friction, such as as soon as you go dvery own a slide at the playground or sled on a snowy hill. The amount of friction transforms depending upon which materials come into contact with one another.Anvarious other thing that can influence friction on an object is the object"s weight. Imagine pushing 2 boxes—one heavier than the other—made out of the same product. You will certainly need to press harder to relocate the heavier box. This is because gravity pulls dvery own harder on the heavier one, which boosts its friction with the floor. In this experiment you will certainly keep the weight of the objects you usage continuous so that you deserve to test various products without worrying around gravity’s effects.

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Materials

Rubber bandStack of 5 or 6 quartersScotch tapeSmooth wooden surchallenge, such as a table or floor (If you carry out not have a wooden surchallenge, you can use any type of various other kind of smooth counterheight or table.)Rough carpeted surchallenge (If you execute not have accessibility to carpet, you deserve to tape dvery own several paper towels on height of your smooth surconfront.)Ruler (optional)PreparationStack your quarters on optimal of one another. Wrap them in tape so they are secured together. Make certain the bottom of the stack is smooth, through no sharp corners of tape sticking out. (These might get captured on the carpet.)Make certain the wood and carpeted surfaces you will job-related with are complimentary from any various other objects or obstructions.ProcedureForm a "C" shape via your index finger and your thumb.Caretotally stretch the rubber band between your index finger and also thumb to form a slingswarm.Still very closely holding the rubber band also, rotate your hand also upside-down and also touch the tips of your finger and also thumb to the wood surface so the rubber band rests simply over the surconfront.Load the stack of quarters right into your slingshot and also pull ago on the rubber band. Pay attention to exactly how far you pull earlier the rubber band; it is crucial to pull back the very same amount each time. What do you think will certainly occur once you release the quarters?Let go of the quarters to launch them. Watch very closely to make certain they slide across the hardwood and execute not obtain launched right into the air or tumble. If the quarters don"t slide smoothly, change your rubber band also and also try aobtain.Repeat the launch numerous times and also watch just how much the quarters go. Remember to make sure you pull the rubber band also back the same distance each time. Do the quarters slide extremely far or do they involved a soptimal quickly? What do you think this tells you around friction in between your stack of quarters and the wooden surface?Now, repeat the very same procedure on the carpet. Be careful not to let any kind of corners of the tape gain stuck on the carpet. How much carry out the quarters go on carpet? Do they go farther or less much than they did on wood? What does this tell you around friction in between the stack of quarters and the carpet? Is it higher or lower than on wood?Extra: Use a ruler to record just how far the quarters go each time. Record all your outcomes in a table and then calculate an average distance for each surconfront. How much carry out the quarters go on average for the wood surface? How much perform they go on average for the carpet?Extra: Try out more test surdeals with in enhancement to lumber and carpet. What if you go exterior and also try the experiment on a tough, stormy surconfront, such as the sidewalk or driveway? What about other surfaces you can uncover in your home? How far carry out the quarters slide on various surfaces? Can you guess whether a surface will certainly have actually high or low friction just by looking at it?Extra: Repeat the activity using various objects instead of your stack of quarters. For example, how do your results change if you attempt the experiment with a large rubber pencil eraser? Remember that an object"s weight determines exactly how a lot friction it will enrespond to, so attempt to usage objects that are around the exact same weight. (You can use a kitchen range to weigh various objects.) Can you discover a things that constantly slides farther than the quarters? What around one that always doesn’t slide as far?

Observations and also resultsDid the quarters go farther on the smooth wooden surface or on the carpet?You should have actually found that the quarters went much farther on the smooth wood surconfront than they did on the carpet.

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Depfinishing on the stamina of your rubber band also and also exactly how far back you pulled it, you might also have released them all the method off the table or countertop! This occurs bereason there is much even more friction in between the stack of quarters and also the carpet’s turbulent surconfront than there is between them and also the smooth surconfront of the lumber. Due to the fact that tright here is less friction slowing them dvery own, the quarters can slide farther on the wood before they ultimately pertained to a stop.More to exploreEffect of Friction on Objects in Motion, from Science BuddiesFriction Basics, by Andrew Rader at Physics4KidsFight Slipweb page through Friction, from Scientific AmericanScience Activities for All Ages!, from Science Buddies