Van De Graff

Safety: Electrons are a dangerous thing because they cannot always be seen, only felt. And by the time you feel them you are probably already on the verge of death. As such, in the name of science, I do these experiments amid the danger for the betterment of all mankind, not just for myself. Selfless, I know. But it's people like me who are to blame for huge advancements in technology and innovation. Dealing with electrical equipment can interfere with the electrical singles occurring naturally within your brain or heart, and as such, can cause brain damage or heart failure. When dealing with electrical equipment, it's always important to be grounded both physically and mentally.

Projectile Project Section 2

                        1.       What was your original construction idea?

2.       What challenges did you face in construction?

3.       Did you stick with your original plan?  Why or why not?

4.       Explain how your device works.

5.       Where and how was this device used in history?

6.       What did you learn by constructing this device?

7.       What principals of physics did you utilize in this device?

8.       Tell about a career where this type of device could be useful.

9.       Could this type of device be useful in getting people to space?  Why or why not

 

 

 

 

 

 

 

 

 

1.VIDEO
       2.The "small" parts of the trebuchet was by far the most challenging to change and adjust. The counterweight, the length of the string, the pouch for the projectile, and the tip of the long arm could change the functionality of the device entirely and they all depend on one another.

3. We stayed with our original plan since it's technically "building" it virtually. It won't be easy putting 80ft of 2x4's back together if we encounter an error when we actually start building it.

4. The long arm holds the string which holds the pouch and projectile. The long arm is then pulled upwards by the 40lb/18kg counterweight on the short arm. With the use of PVC pipes and metal pipes, the friction to pivot the long beam is almost negligible...which is necessary since the goal is to swing the long arm as fast as possible.

5. Trebuchets have been used from the 12th Century to modern times. They have been used for throwing dead, infected bodies to cities, boulders to destroy castles, or pumpkins. 

6. As we built the trebuchet, we learned a couple of things: new tools and how to use them, how dangerous it is to build one, how it gets frustrating when measurements are off, and how fun and satisfying it becomes after building it. Other than the ones previously listed, we learned how to have fun with building it... even though it's not perfect.

7. We used the law of gravitation(how gravity affects our trebuchet).Other than gravity, the law of conservation of [insert Physics topic] is/are also used(Come on... almost all of them affect the trebuchet).

8. If you are a high ranking officer in the military, and destroying historic castles or cities with boulders or dead bodies is still a "thing:" then a trebuchet would be the perfect "historical match" for your job, per se. Other than that... a Physics teacher/professor could use this device as a project for his/her students. 

9. Would this type of device be useful in sending people into space? It depends... Since we just learned about "Escape Velocity," the velocity the trebuchet can fire a projectile must be more than, or equal to approx. 25,053 mph: a velocity enough to kill a person, but it will do the job. Other than the trebuchet's lethality, building the trebuchet itself would be hard to accomplish.

To test our trebuchet, we started off doing test fires at random. Seeing if the ball launches too early or too late determines whether if we have to change the angle of the tip of the long arm. The lower the angle of the metal tip relative to the horizontal of the long arm tip, the later the ball is released. With the right angle, maximum distance traveled by the projectile can be achieved. The only problem with this is how to keep the metal tip from changing its angle.

Saftey Concerns

When building a trebuchet, the fear of getting one's face smashed by a 2x4 piece of wood is a good incentive to be careful. Power tools such as the miter saws we used is a hazard to the untrained user. Nail guns become as intimidating as an AK-47 if a person holding it does not know what he/she is doing. Heavy lifting is required, so closed-toed shoes are highly recommended. To remain intact, one must be alert and careful when handling materials and tools. When firing projectiles, the "trigger" must be at least 2 meters away from the trebuchet since many things could go wrong. Warning people in front of the projectile trajectory (unless the goal is to kill or destroy), is highly recommended when firing the trebuchet. The stability of the trebuchet frame must be constant when the trebuchet is firing. To avoid injuries and casualties (assuming the target isn't a city or a castle), one must be on the mindset of "what if [insert worst case scenario] happen(s)?"

Power lab

Procedure:
In this lab, we use electrical meters to calculate our average home's power usage
Question:
1.If you ran up the ramp in half the time of another student of equal weight you did the same work but used twice the power. Explain. This is because p=w/t. The smaller number "t" is the bigger number power is.
2. If the height were reduced by half, the work would be less but the power would be the same
3.Greater power is not necessary, it uses the same amount of power.
4. 66 gallons
5. .134 hp for the light bulb. 150 kW for the engine

Hooke's Law

Procedure:
In this lab we demonstrated the Elastic Limits of Springs and Hooke's Law by adding weights to a string and letting gravity stretch it out. Based on how far it stretched and the actual length of the spring, we were able to calculate the spring constant of the spring.
Questions:
1. Things that may have causes errors in our results was that we couldn't measure the exact changes in spring stretch because sometimes it was a really small change and we didn't have the means of measuring something so small
2. More precision can be added to this apparatus by containing the spring a tube so it can not sway or move when adding weights to it.
3.If you overstretch a spring or rubber band it can either break about and/or it will never return to the shape it once was. It would affect our result because the length of the actual spring without any tension would be longer than normal
4. It looked like a linear graph and the slope represents tension being put on f the spring
5. The minus sign means the force is opposite of the displacement. Meaning if you compress the spring, the spring pushes back at your and vice versa
6. No rubber bands do not obey Hooke's law
7. Most physical factors contribute to the spring constant, i.e. material, weight, mass, length etc.

Transger of Energy lab post 3

Question 1:
Most of the device was pretty even in turns of energy usage but if there was one part that was exceptionally wasteful, it would have to be the gun shooting the tennis ball. Because the gun has a vast amount of energy and power but all it does is push a tennis ball ever so slightly to right.
Question 2:
The transfer that was most efficient was when the tennis ball crashed into the wood blocks and made domino-like effects. The reason I think it was the most efficient is because the tennis ball was relatively slow moving. Yet, it was still able to knock down many big and heavy wood blocks by making a domino effect
Question 3:
I've learned many things about this device, especially how difficult it must have been for the TED talk people to construct something of such magnitude. Every little step has to be perfect and tested many times. Every time you test it you must set it back to it's original state. It's a very tedious and time consuming process, but rewarding when everything works out.