Newton Lab results

1) acceleration vs. force 1

d1=0.8 cm d2=3.0 cm dt=24 cm
t=1/30 s a=1.6m/s2
v1= 0.24 m/s v2=0.9m/s

2) acceleration vs. force 2

d1=2.9 cm d2=9.0 m dt=58 cm
t=1/30 s a= 5.6 m/s2
v1= 0.87 m/s v2=2.70 m/s


3) acceleration vs. force 3

d1=3.5 cm d2=7.3 cm dt=35 cm
t=1/300 s a= 5.28 m/s2
v1= 1.05 m/s v2=2.19m/s

4) acceleration vs. mass 1

d1=0.8 cm d2=3 cm dt=24 cm
t=1/30 s a=1.6m/s2
v1= 0.24 m/s

Best Cannon

The best cannon would be sturdy and powerful enough to launch an object over a great distance. The cannon should be made with a long tube "neck" to get the greatest amount of distance. The tube should also be narrow so that when the propane is set on fire, it will push the object farther. The angle at which the tube is placed is also important. If it is parallel with the ground, the object will not go very far. At, for example 45 degrees, the object will go much farther. "With every reaction, there is an equal, opposite reaction". Therefore if the cannon has a lot of firepower, it should be constructed to withstand the opposite reaction.

Newspaper tower

Using only newspaper and tape, each group tried to construct the highest standing structure. From previous research, everyone knew that their tower needed proper support in order to stand. Our group rolled pieces of newspaper into very narrow tubes and stuck them together with tape to form a tall pole. It was actually the tallest in the class because we left almost nothing for the base and supports. So, with the remaining pieces of newspaper, we constructed  stick-like supports that were taped to the bottom of the tower. Essentially, the stick supports were meant to stop the tower from leaning over and falling, but they were just too thin and flimsy. Our tower did not manage to stay standing because the base did not have enough weight to keep the structure on the ground, and because the stick supports were not thick enough to keep the tower upright.

The Tallest Structure

The tallest structure in the world is the "Burj Khalifa" located in Dubai. It stands 828m tall, and it took aproximately 5 years to complete. The tower gets slimmer as it increases in height which keeps it from falling over. The base is supported by a concrete mat 3.7 meters thick. Concrete in the base has to have a high density to support the structure's weight.

The "podium" area of this structure is used as the center of gravity. Most of the materials making up the structure are located in the center. The weight prevents the tower from tipping and making the height of the structure physically possible.Also, a Y shape makes up the core of the Burj to keep it stable and reduce wind forces. Coloumns are used to strengthen the walls and other mechanisms that help resist weights.

Projectile Motion Questions

Physics questions

Textbook pg 72 # 54, 56, 58, 60, 62, 63

aerodynamic egg glider

I think a good design for an egg glider would be to use the 25 straws to make a skeleton of the glider. Then cover the skeleton with newspaper so that air can be trapped, slowing the glider's fall. The skeleton would have 2 wings like a bird. Then loosely cover the wings with newspaper leaving room for air to accumulate. A central compartment would be designed to hold the egg. This protects the egg from all sides so that when the glider reaches the ground, the egg won't break or anything. It would be located in the middle of the glider so the centre of gravity is balanced across the whole structure. When it is thrown off the school, the wings will catch air and slow the decent. The glider will float to the ground, acting as a parachute for the egg and preventing it from breaking.

5 results from walking graphs + translations

 1

This was the first graph we walked and it mapped distance. Therefore, the higher the line is on the graph, the farther we go from the motion detector. A straight line means we stand still and decreasing/increasing lines means going closer or farther from the detector. So, we start at 1m away from the detector, and walk 2.8m away from the detector in 3 seconds. Then stand still at that spot for 3 seconds. Then walk back to 1.8m away from the detector in 1 second. Then stand still for 3 more seconds.

This is the second graph we walked, also in distance. We start at 3m away from the motion detector and move to 1.5m away from the detector in 3 seconds. Then stand still for 1 second. Then walk 0.5m away from the detector in 1 second. Stand still for 2 seconds. Then walk back to the origin of 3m in 3 seconds. However, our group did not stand at the exact spots and it got messed up at the end.

This graph calculated velocity and was probably the hardest one we attempted. Basically, vertical lines indicates the direction and the speed at which you go in that direction. Horizontal lines mean keep a constant speed. Start by standing still for 2 seconds. Then walk backward at 0.5m/s in less than a second. Keep walking backward at 0.5m/s for 3 seconds and then stop for 2 seconds. Walk in the other direction at 0.5m/s and maintain that speed for 3 seconds. This was extremely hard as keeping a constant speed was very difficult.

Another velocity graph which was as difficult as the last one. Start moving backward increasing speed as you walk peaking at 0.5m/s for 4 seconds. Stay at the peak speed for 2 seconds. Go forward at 0.5m/s in 3 seconds. Move backward decreasing speed until standing still in 1 second.

The last graph which mapped distance. Start a little less than 1m away from the detector and go to 1.9m away in 3.5 seconds. Stay at that location for 4 seconds. Then walk backward to 3.2m in 3.5 seconds.

Walking the graph lab

Today, our class changed rooms and did the "walking the graphs" experiment. We were split into groups and each got a laptop and motion detector. Then we opened preset graphs to walk them. Most were motion graph where the motion detector detected our movements and plotted it next to the onscreen graph. We were supposed to match the motion preset graph as closely as possible.
Heres our first attempt at the first graph (b):

As you can see, we were pretty close!
Some graphs werent as simple however. For example, we got a graph that plotted velocity. Walking at a constant speed was difficult, and then changing to a higher speed fast was even more hard.
Heres our attempt:

its pretty bad, but it was extremely hard.

Right Hand Rule 1 + 2

The Right hand rules are used to determine the direction of current and the north and south poles of a conductor or coil. The Right hand rule literally uses your right hand to measure these things. With a conductor, you wrap your right hand around it and bend your fingers in, similar to a 'cat'. The direction in which your thumb is pointing is the direction of the flow of current. The fingers symbolize the invisible magnetic field around the conductor.

This is known as the Right hand Rule.

Concept Mapping

Today, our class experimented with a new method of learning called "Concept Mapping". Instead of writing down notes, you link ideas together with verbs in a sort of web. This is our groups concept map:

The title "electricity" is placed in the middle with different ideas such as "ohm's law" and "kirchoff's law" linked to it. Then, there are links to similar subjects with verbs. For example, voltmeter is connected to volts with the verb " measured with".

       10 things to know for this unit:
1. Ohm's Law
- The VIR triangle
2. Kirchoff's Law
- All the formulas for calculating voltage, current, and resistance in series and parallel circuits
3. e= 1.6*10^-19 C
4. Current = Q/t
-Q is coulomb charge
- t is time in seconds
5. How to draw / understand circuit diagrams
- resistor symbol
- power source symbol
- where the ammeter and voltmeter goes
- ability to identify series from parallel circuits

Ohm Vs. Kirchhoff

Ohm's law states that voltage has direct relation to current. When voltage is high, so is the current and vice versa. Also, resistance is stays the same in different circuits. These concepts can be explained by the simple formula : V=R*I. One can easily remember this formula by drawing a triangle, placing V at the top and R and I on the bottom.

Kirchhoff's law is used for complex circuits and uses lots of formulas that correspond to either series circuit or parallel circuit to determine current, voltage, and resistance. In a series circuit, current (I) can be expressed as I(t) = I(1) = I(2) = I(3) =...=I(n). This means that throughout a series circuit, the current stays constant. In a parallel circuit, current is expressed as I(t) = I(1) + I(2) + I(3) +...+I(n). The current in a parallel circuit is the sum of all the loads' currents.
Voltage, in a series circuit, is expressed as V(t) + V(1) + V(2) + V(3) +...+V(n). In a parallel circuit, voltage is expressed as V(t) = V(1) = V(2) = V(3) =...=V(n). However, resistance is a bit different. In a series circuit, resistance is calculated as R(t) = R(1) + R(2) + R(3) + ...+R(n). In a parallel circuit, resistance is expressed as 1/R(t) = 1/R(1) + 1/R(2) + 1/R(3) +...+ 1/R(n).

Energy transformation

Voltage, also known as "potential difference" can be measured by a device called a voltmeter. 

 Similarly, current can be measured with an ammeter. ( coloumbs charge / second)

We also watched a small video explaining energy transformation from a battery to the circuit. The battery charges electrons and sends them to the load. There, the electrons let off energy which transforms into heat. The electrons then travel back to the battery to become charged again.

Favourite Roller coaster Design Feb 9 11

My favourite roller coaster design was the one themed around the movie "Inception". Basically, the group took different events from the movie and created a roller coaster with it. For example, many destroyed buildings are present in Inception. So, the coaster features a track that twists and turns around similar buildings. There was also an airplane in the movie that the characters were traveling on. Around the top area of the roller coaster, the group constructed a small airplane replica which was quite interesting. Overall, this roller coaster had an interesting theme and built solidly.

Energy ball feb 6 2011

Today, our class was split into groups and experimented with "Energy Balls": little ping pong balls that lit up and made sounds when you touched it. Each group was given questions about the energy ball to discuss. Then, the entire class got together to make parallel and series circuits. We learned that a parallel circuit had multiple ways for energy to flow through and a series circuit had only one.

Compared to regular note taking, this experiment was quite fun.