Top Ten Physics Situations When Setting Up A PARTY!

1. Letting People In

Alright, This is one of the most important parts of a party, letting the people come in. When people arrive, you don't want to always be at the door to open it or hold it open when they come in. You need a door holder! A door holder needs/does prevent the creation of a force for a torque, a rotation. This door holder creates a lever arm. A lever arm is the perpendicular distance from the axis of rotation from which the force is applied. This door holder, which is now a larger lever arm helps overpower the force from the door (Torque = F*leverarm). The best place is to put the door holder at the end of the door where the handle is, this creates such a large lever arm to hold the door open. Now your guest can join the party with their full hands easily!

2. MiniGames (Bowling)

You need games at this party! Luckily, you found a bowling ball and 5 pins! You set the pins up 20 feet away from a line of tape, where you start to roll the ball. When you roll the ball, the ball knocks down the pins, you then wonder how!? According to Newton's First Law, an object at motion/rest tends to stay at motion/rest until acted upon another force. The pins were at rest and the ball was in motion, after you rolled it. When the ball hits the pins, the pins went from rest to moving, from the outside force from the ball, and the ball was stopped by the outside force which was the pins. This is going to be a great minigame for a party!

3. Water Guns!

Now this party is getting more exciting! you found a set of 4 water guns! You fill them up but find 2 of the 4 don't push water out as hard. You find out that the 2 water guns don't push the water out with a lot of force for its mass. Hey! Newton's second law describes this. Acceleration=Force/Mass. Since the water guns don't push the water with great force, they won't have that great of an acceleration. The party people with these water guns are not going to do so well, so don't tell them!

4. Horsey Races!

Of course there has to be a race in a party! Now, running is not that fun so you think of adding another person to the teams. Yep, you think of riding on each others backs! You want to win though, because this is your house and no one beats you at your house, except you! To win this you think of a strategic plan. To win, you tell your partner that you ride on to lean a little forward, this is to balance the weight distribution of the both of you. This is an example of putting support under your centre of gravity. If your partner didn't lean forward, you guys would have so much troubles and fall backward. Falling backwards is the cause of having a unsupported centre of gravity, which creates a torque the side that has the most.

5.1 Wait What?

The bowling ball doesn't roll on the grass outside at all! This is because the grass gives to much friction for the ball to roll. This is another example of Newton's first law, so you make a wood floor out of board from under your house you haven't used yet.

5.2 Slip N Slide

This fixing of the floor of the ball gave you another idea for the party! A Slip N Slide! Here you lay out a tarp, you spray the people down and off they go slide down it. At the very end of the tarp you put pillows so people don't hurt their selves. Why did you put pillows there? If you have a person slide down, they will end up having friction equal the same amount of force they slid down with. This will equal to 0N of force so the person will be at constant velocity at equilibrium. They won't be able to stop! Thanks to the pillows though! This is also an example of moving boxes, if the box is at 0N (equilibrium) it won't be able to move because the friction force equals your force. If you add more force, then it'll move.

6. Moving Dangerous Things Out of The Way

Now you notice the sharp cube in the way of running to the slip n slide. You decide to push it out of the way. While pushing it, did you know it also pushes you? Yes, this is true, Newton's third law states that every action has an equal and opposite reaction. So when you push on the box, the box pushes you. Just like when you walk you push ground back, while ground pushes you forward. The pushing on the box is the action and the box pushing you is the reaction. 

7.  Cotton Candy Machine

You found your old cotton candy machine and set it back up. Once you did so you find out that you put the syrup/powder on the outside of the rim of the machine. When you turn the machine on, it spins slowly, why? You need to be making a lot of these fast! Well, Angular momentum is the momentum in a spinning/rotation. To have a greater this, you need to increase your rotational velocity, but how can you do so when you have a set angular momentum (conservation of angular momentum). You decrease the rotational inertia, to do this you pour the powder closer to the centre of the machine. Now it spins so much faster! Angular Momentum= Rotational inertia*Rotational velocity. Conservation of Angular Momentum is: Angular Momentum=Angular momentum (Increasing or decreasing one of the 2 factors.

8. Towels!

You used your towels last week and you still haven't washed them! You pop them into the washer, and start to think how does a washer work? Washers cause the clothes to become in the centripetal force, which makes a body object follow a curved path. Next the water is coming from inside the machine from those holes you saw. This water follows a tangential path, straight path. Since both of opposite, this allows the water to get to the clothes and wash them. 

 9. Lights

Alright. You think of when it gets late during the party. You need some cool lights. You find some of your old christmas lights and hang them up. Then you plug them in and notice they all don't work. This is because of one light bulb is blown, but why does one affect them all? This is because they are set up in a series circuit, so since the light bulb is out it can't complete the circuit to flow current to the others. Dang! You don't have extra lights! You find some extra wire though and do some engineering. You take the lights apart from the wire and place them in a parallel circuit. This makes every light work on its own wire but causes the current and voltage to go up in the whole system.

10. BALLOONS!

You got 30 minutes until your guest arrive and you haven't set up the balloons! You forgot to get helium and you don't have time, so you start blowing them up. Since oxygen is in them, all the balloons do is fall o the ground. That's boring you think. So, you start shaking and rubbing them only our head, this causes them to charge through friction, and your hair steals the positive charges and your balloon is now negatively charged. When you go near a wall the positive charges of the wall attract to the negative charges of the balloon. When the positive charges separate from their negative charges in the wall, the wall becomes polar. Coulomb's law states that F=kq1q2/d^2, so since the attracting charges are closer, the attraction force will be greater than the reeling charges (the negatives) and attract the ballon to the wall. You do this like a ton of times and now your balloons are all on the wall.

I hope this helps you learn more physics while setting up a party. I also hope you learned that this is the way to set up a cool party! 

Peace

-Physician Gannon

Motors

What's a Motor

A motor is a contraption that has a current carrying wire and magnets. In this case, we made motors out of wire, magnets, and battery. The current carrying wire, current from battery, feels a force in a magnetic field and the force causes a rotation, or torque. This is how my motor worked.
*A motor has current bearing wires and magnets.

My motor looks like the one in the picture above. It span freely on its own in the paper clips and the paper clips plus the other materials all helped the motor become a motor.

The paperclips were attached to the ends of the battery, they were used as the stand and conduct current to the wire. The wire was the current carrying wire that span as a result of the current flowing, since it was in a loop. The magnet supplies the change in magnetic field which causes the torque, and the battery supplies the current for the whole contraption.

The Making

To make this fully functional, I had to scratch the arms (paperclips) and the wire in a certain way. I made the paper clips in a certain way, like the picture, to hold the wire freely in the hole and scratched to allow current to flow through the wire. Now the wire was scratched on one certain side to also allow the current to go through freely. This is because the copper on the wire tops (the coating) would cause no current to go through and if we scratched it all over, it wouldn't make a complete circle when spinning. (right hand rule applies here).

This wire spins because of the moving charges and current going through it. The magnetic field is going up, the current goes across the wire, and so the force of the loop is to the side of the wire, which creates a torque and spins the loop.(Again, the right hand rule)

All of these moving charges feel a force from the magnetic field and they move away in such a way to the field, perpendicular. 

One whereabout you can find a motor like such is in an engine. Thick wire, when you turn on the current will cause a spin to the propeller and cause the push against the water so the boat can accelerate forward, or back.

Wind Turbine

We Made Electricity!
So, Recently in class we were making wind turbines. It was a fun activity and what we did from it is generate electricity. Here are all the materials we used to make our turbine:
-Boards of wood
-2L Soda Bottles
-5 Bolts 
-5 Magnets
-Styrafoam
-Wood Stick
-Glue
-Copper wire

The wood was for the base of our wind turbine. Our group made it look almost realistic to a windmill. The soda bottles were cut into fourths and used as the wings for the turbine where the wind it. The bolts were glued into the styrofoam, as our wings were put in to rotate on, with our magnets attract/stuck onto the bolts. This helped for the stick to be glued onto this styrofoam with everything on/attached to it so when the magnets rotated over the base, the copper wires were hit by this magnetic field.

Physics Concepts

Let's go back to day 1-3; Newton's Laws. All 3 of Newton's laws were reintroduced and shown in this experiment. The first one; an object at rest will stay at rest unless acted about an outside force, was used in the case where the wind from the fan blew on the rested wings and made them rotate. Newton's second law states that more force will cause more acceleration, so the faster the wings were rotated, the less mass didn't matter. The third law, every action has an equal and opposite reaction was used in the case that the fan pushed wings, wings pushed fan.

There's one physics concept recently exampled that is the most important one in this case is electromagnetic induction. The coils of wire, when a magnet is moved around them, causes a change in magnetic field which induces a voltage and causes a current. This is what actually generated our electricity.

Our WindTurbine:

Here is our magnet placement in our wind turbine. We had 5 magnets attracted to 5 bolts glued into the styrofoam. These magnets, when rotated by the wind, rotated over our 5 coils of wires as you can see were taped and glued down to the base of wood. When rotated over the wire, the magnets caused a changed in magnetic field and induces a voltage and causes a current, which generated our electricity. We didn't have a picture of the coils close up, but here is the two in one for the magnets and coils, the process of electromagnetic induction.

 Here are our wings for the turbine. Our wings were made out of a quarter of a 2 litre bottle. these wings helped us rotate the magnets over the wires. The reason we chose big wings/bottle was because our middle/styrofoam magnets circle was a big plan so we needed much wind to be forced onto the system so it will have an easier time rotating and forced.

Here is our full model. We used tall wood to keep the wings from hitting the ground or table. We also wanted to make our wind turbine look realistic, and I think we would've won for a creativity section.

This is our video of our turbine working! We generated both .007V&A. This is too low to light a light bulb though, because we didn't generate enough voltage. Don't worry, we'll work on that!

Some things that caused us to get a low voltage was:
1. Our magnets when rotating kept hitting the coils of wires which caused the wind turbine to not spin as fast or consistent. This was friction.
2. Our coils got messed up while spinning them, so that could've been a factor of not generating not enough voltage.
3. The magnets could've been poled differently, which generates different magnetic field which would cause the current to be back and forth and not generated correctly.

If I could do this project again, I would make my base the same. In the generator area, I would make a bigger coil of wire and have the magnets spin inside of it instead of over it. Going through the coil has a better electromagnetic induction because it changed the magnetic field more instead of over it. I would also make sure everything is perfectly measured and equal torques of the wing side and opposing side of the rotating part. This all will cause a smooth, better running and electricity generating wind mil.

Unit 7: Opposites Attract

Like Paula Abdul said perfectly in her song; opposites attract! That's right, this unit was all on magnets! If that's what you were thinking of when I said opposites attract.
Alright lets get into magnets!

Magnets

Magnets has 2 pole, North and South. What!? This is just like our earth! Except in our earth, the magnetic poles are flipped, which means South is our North and North is our South; confusing, yes I know. These poles direct the way the magnet attracts/repel:

As you can see the north pole forces out, while south pulls in. This causes the opposites attract and like not to attract, since like 2 North pushes away from each other.
Going back to our earth being flipped, what I meant was compasses, they point North right? Wrong! Compasses actually align with the magnetic field of the earth and follow the arrows. Looking at the picture above you can see that the arrows of a magnetic field around the object go South. So North is our South.

Motors

Motors in the unit of magnets? I know, I thought the same thing, but motors actually run by magnets. A motor is a current carrying wire in a magnetic field being forced in a certain way. Motors use Alternating current for it to run. Here is diagram for motors:

ElectroMagnetic Induction

Big Words! Electromagnetic induction is charging a wire/creating a current and voltage with a source of a magnetic field. We see this in our everyday lives, but just don't notice it. Traffic lights have this! Here's a video over how electromagnetic induction works in a traffic light:

Transformers

Transformers help us out so much. They are in our laptop chargers, wire poles, and other appliances. A transformer is a tool in a wire setup that either steps up or down the voltage and current for an appliance. Transformers have 2 sets of coiled wires, the first set is the primary coil and the secondary coil is the second one. The first one, lets say has 100 coils and supplies 10V from the wall, your computer needs 1V to run, so the secondary coil will have 10 coils because P=Psecondary. These transformers work through electromagnetic induction also. 

Unit 6: It's Electric!

Charges & Polarisation

Charges, ok, Im pretty sure most of you know the two charges. Positive and Negative charges! These two charges attract one another, but like charges (2 positives/negatives) repel. When the charges connect/complete the circuit, a flash, noise, and heat is given off, like lightning. Here we learned that and Coulomb's Law which is Force is equal to K(constant)*charge 1*charge 2 all over the distance between the charges squared. 

Polarisation is when in an object the positive and negative charges are neutral but separated from one another. This is how water is attracted to a rubbed pole or how our hair sticks up when we rub a balloon on it. The actual reason is the balloon and cloth rubbing the pole is stealing, through friction, our electrons. When the balloon is pulled close to a wall or our hair it attracts the positive charges and sticks.

Another way to steal electrons or charges is through inductions, which is not even touching the object.

Electric Fields

An electric field is when an object emits either a repel or pulling in force. The arrows you see in this next picture show where positively charged charges go from the certain particle. 

Shields can help too. Appliances are not supposed to get more than one type of charge or else it will be ruin. This is why we put our appliances in a metal covering. Metal is neutrally charged and has property that takes in a charge to balance it out. This is known as an electric shield.

Electric Potential & Capacitors

Alright, Now into some more information about equations, but first let me tell you what electric potential is. Electric potential is potential energy over charge, this is also known as volts and is measured in volts. Difference in this is going from high to low just by subtracting the low FROM the high volt. If there is a high difference there can be a shock and if you are causing the connection from high to low, lets just say shock. 

Capacitors are what cause flashes and other useful tasks most of our appliances use/perform. It's two plates that are charged timely and when you press the button for the picture or flash, causes the plates to touch and a flash happens. This is again the attraction of like charges.

Now we get into Ohm's law which is Current (I)= Voltage(V)/Resistance(R)

We can calculate any of the three if we have enough info.

Current

There are two types of current: Direct Current and Alternating Current. DC is when the current flows in one direction while AC current is go back and forth. It's funny because the electrical company doesn't supply us electricity or voltage, they supply us with current.

Circuits

Like current there are two types of circuit: parallel and series. Parallel are where each appliance is wired directly to power/voltage source while series is where everything is connected in one line. When one appliance turns off or is taken out of a series line, the rest following it from  high to low are turned off. In a parallel circuit, this doesn't happen, they all stay on. 

Fuses, they help prevent fire. You can put them at the very beginning of parallel circuit or ending, never in a series circuit. When too much current is going through them they completely break and cause the whole circuit to turn off, which prevents fire.

Mouse Trap Car

Mouse Trap car? What could this be? A Moving mouse trap? Yes!
Our assignment was to create a car out of anything we wanted or gathered and make it powered by the force of the mouse trap and it had to go 5 meters.

How we constructed it

For this project, Winston was my partner. What we did was construct a 4 wheel car, using metallic disks for wheels. The main body of the car was made out of wood we got from our local Lowes store, and so were the axils. For the axils to spin in, we stuck them through some pvc pipe and fastened it to the car's body. Then, we hot glued the mouse trap to the car and attached a lever arm with a string, which we later changed to rubber band. This rubber band was to wind up on the back axil, pulling the lever arm of the mouse trap, so it could, when let go, run by being pulled by the elastic and mouse trap combined. We made sure to not tie it onto the axil because if we did, once done unwinding, it would cause the wheels to stop.

Video of our car

In this video, are car just made it to the 5 meters mark, but then rolled back an inch.
We did more test after this video, but with this video our time was about 10.03 seconds. We calculated the velocity of the car to be, using v=distance/time, 0.49 meters per second.

Picture With Labels

INSERT PICTURE

So what does this have to do with physics?

This mousetrap car brought all of the 3 of Newton's laws together in one project. How? Well, Newton's first law states that an object in motion tends to stay in motion unless acted upon another force, once we got that axil in motion from the mouse trap, it will want to continue to stay in motion, or rotate. The car also was affected by this, once moving it was moving, but the friction from the pipes and the ground made the car slowly slow down which was the "acted upon another force". The only thing that could prevent that is friction with the ground. Adding the free rolling wheels reduces this, but frictional forces on the axil must be reduced to maximize free rolling.

The wheels pushing the ground back, the ground pushing the wheels/car forward, and the rubber band pulling the axil, the axil pulling the rubber band, were both examples of Newton's third law. This law states that every object has an action and reaction force. This pushing car also explains the acceleration=Force/mass. This was Newton's second law. The bigger the mass, the less acceleration, but the bigger the force, which we did with a rubber band increased our acceleration, but since we had a big mass, it didn't cause that much of an increase.

More about the wheels, in the latest units we learned about rotational inertia. Our wheels for our car were somewhat bigger than others, why did we choose them big? Doesn't more mass cause less acceleration? Yes, more mass does cause less acceleration, but our wheels were very thin. The more mass not he outside of the axil would cause more rotational inertia, which is bad, meaning it wouldn't rotate easily. The reason we chose them having a bigger diameter was because this increased the tangential velocity, which is the time/speed it takes to do one rotation on the outside. Since we had the force in the axil of the wheel, the outside had to spin faster to do what one slower rotate in the middle did, so our car went, or was supposed to go faster, this is explained more later in this blog. Also, why our axil rotated was because when the mouse trap set off, it caused torque which was rotation. We added a longer lever arm to increase how much of the axil was going to spin more, not to increase the force, because when lever arm increases F decreases. the lever arm was to increase the rotational velocity of the axil.

The mouse trap stored elastic potential energy when it was set, this energy was conserved. It was conserved because once it was released it was transferred into kinetic energy, which the ability/wanting to move, which the car did with this forced spinning axil. This spring on the mousetrap was setting off force in an upward then downward way while the distance of the car was going forward. We know work=force times distance, but the force and distance aren't parallel. Potential and kinetic energy are equaled to the change in work, and since there is no work, we couldn't find how much of these energy there was in this car. We can't calculate the force because it's in different ways/areas.

Reflection

Our final car changed from what we planned. What we planned was a small car, but powered the same way. We ended up with a big piece of wood as the base. What caused this big car to be big was we needed materials so we rushed to get them not thinking of the physics behind this project at the time, once we started, then is when we knew we should've went smaller. The major problems was that our axils for our wheels didn't have anything to rotate in, except some hoop we made from sticking tape together. We resolved this problem by using pvc pipe so the axil ran smoothly through it. If we did this project again or any building project, we would probably go smaller, depending on the project, think of all the physics concepts before the materials, and make sure everything fits perfectly once we get the materials, because if you have a smaller axil than its hole to rotate in, then it's going to start turning a lot, which wastes energy. 

Unit 5: Do you work?

Alright! This unit was short, which made it great! This unit was all about work, power, and energy. Let's get into this:

Work & Power

Work is found by multiplying distance and force not he object. The distance has to be the height the object is being forced on, not how long it goes. Work is measured in Joules (J) and the force and distance have to be parallel for there to be work. So, if I walked up the stairs, let's say I'm 600N and went up a 20m stairs, I did a total of: (20*600)=12000Joules of work. 

Here the waitress isn't doing any work because the distance and force aren't parallel:

Power is found by dividing work by the time it is done in. So, with my stairs example, I did a total of 12000J work, let's say it took me 10 seconds to go up the stairs, 12000/10=1200Watts. Yes, power is measured in watts.

Here is a video of our project explaining work and power:

Energy

Work, Power, and Energy are all related. We can find kinetic and potential energy with information from power and work. The change in kinetic energy is equal to the change in potential energy, and equal to work. If not given any detail from work and power, the kinetic energy formula is 1/2mv^2. m is mass and v is the velocity of the object.

Kinetic energy and potential energy are conserved, and you will see that here:

When high above ground, you have potential energy, but when falling or dropping, you gain kinetic energy but lose potential energy. Let's say you have 1000 PE, when you're 25% down the drop, you have 250 KE and 750 PE, vise-versa for where you are in the drop. This is the conservation of Energy.

Machines

This is the last thing we learned in the unit, I told you it was a short one. Machines make work the same, but easier. It doesn't reduce it, just reduces the force that you have to do by increasing the distance. This is a good example of ramps. Ramps to get heavy stuff in a truck help you do so by letting you go up a bigger distance with less force.