Egg Drop Lab...SUCCESS :)

This week we did our Egg Drop Labs! I found this to be a very fun, interesting, and yet kind of challenging experiment to do because Kawai, Lydia, and I weren't 100% sure if our egg was going to survive! We used a 33 cm shoebox as our device.  We glued lots of cotton balls to the inner surrounding walls of the box.  After the box was all cushion-ized, we took a smaller box and glued cotton balls into it. This small box would be the object that held our egg in place.  When we received the egg, we wrapped it in black felt and taped it so that it was secure.  Once we were finished wrapping our egg in felt, we placed it into the small box and closed it.  We then put bubble wrap between the cotton balls on the inside of the bigger box and the bottom of the smaller box. We taped the small box to the shoebox.  We closed the lid of the shoebox and taped it so that it would not fly off during the drop.  If you watch the first video above, it shows how our egg was dropped.  In the second video, you can see that our egg survived the fall!  The reason why our egg survived was mainly due to the cotton balls.  We chose to use cotton balls because we knew that it would absorb the shock of the fall.  I really liked this lab because it was like a mini project and there was a little bit of suspense right before our egg was dropped.  I also liked seeing the various devices that the other groups created.  After all the eggs were dropped I came to realize that this lab wasn't as challenging as we made it to be.  One group had a very simple yet effective device.  They had three sponges.  They cut a whole in the middle of one of the sponges just enough for the egg to fit in.  After placing the egg in the whole, the surrounded the sides with the other two sponges (one on each side).  They then rubber-banded the three sponges together and dropped it! To me, this was the smartest device of them all because it was light in weight and it had LOTS of cushioning which would make the contact time of the sponge and the ground a lot longer than a shoebox would.  But, in the end, I'm just glad our device worked and our egg survived.:)

MOMENTUM!

I finally understand what momentum is and how you can calculate it.  Like I've mentioned in previous posts, momentum is calculated by multiplying the mass of the object times its velocity.  For example, the picture above is of my eraser.  Let's say that this eraser was 2 kg (a very heavy eraser).  If I were to throw the eraser and the velocity it was moving at was 2 m/s, I could then calculate the momentum of this eraser.  The momentum would be 4 kg m/s because I multiplied the mass by its velocity.  We use momentum in our everyday lives.  I am glad I know how to calculate momentum now!  I'm glad I learn something new in Physics everyday :)

More Stuff on Momentum

This week in Physics, we learned more about momentum.  On Wednesday we were suppose to do a lab about collisions to help us learn more about momentum, but I was sick on that day, so I'm not exactly sure how to explain anything about collision.  But, I can explain a little bit about the Law of Conservation of Momentum.  This law states that momentum cannot be created nor destroyed, it only changes forms, momentum in then will equal momentum out.  From this week, I learned the momentum is a vector/  To find momentum you must multiply the mass of an objec by its velocity (P = mv).  The units we use in this equation are kg m/s.  I also learned about impulse and how it contributes to momentum and force.  Impulse is the change in momentum (delta P).  This is then plugged into the equation of force, which equals the change in momentum/change in time (delta P/delta T).  This is what I learned this week in Physics.

My Thoughts on Momentum

Our next chapter we will be covering is momentum.  In order to begin this new unit, Mr. Blake wanted ut to make our blogpost about either what we think momentum is using our own personal knowledge, or doing research on it.  Because I don't really know anything about momentum, I did some research.  I first looked up the definition of momentum and dictionary.com gave me: "the force or speed of movement of an object".  I then looked in our textbooks for more answers.  The first thing in the textbook about momentum was linear momentum.  Linear momentum is defined as the product of the mass and velocity of an object.  The example it gave me basically said that if you catch a fast enough light-weighted ball and compare it to catching a heavy, slow moving ball, then you will move with the same speed.  This helped me to learn a little about momentum.  Before this small research, I only knew how to use the term "momentum" in speaking, but I never really knew what it was.  Now I know something about it!

Friction!

This weekend, I had to move a couple of these big boxes from my living room into the office.  My living room floor is covered in carpet.  The boxes were way to heavy to carry by myself, so I decided to push them.  Although I am not exactly sure what the precise amount of the forces acting upon the boxes was, I do know that the forces that were acting upon it was weight (mg), normal force, the force I used to push the boxes, and also friction.  There was friction because the boxes were on top of the carpet, causing an opposing motion to my force exerted on the boxes.  Many times in the past I have pushed objects across floors, but I never really thought of why it was harder to push things across certain types of surfaces.  I now know that friction is an important part of motion.

Force

In Physics, we learned about force.  A force is a push or a pull.  This week we learned  about how forces affect objects.  In learning this, we used free body diagrams.  In the picture above, there is my contact solution box resting on my dresser.  This box can stay at rest because it is balanced and no outside forces are acting upon it.  The forces which make this object balanced are its own weight (mg) pushing down and the normal force (N) pushing up.  These two forces equally pushing against each other is what makes the object balanced.  Right next to my picture of the box at rest on the dresser, there is my free body diagram.  Free body diagrams (FBD) helps us to see the forces and how they are affecting the object.  There are two arrows in my FBD, which are the weight and the normal force.  This is another way of explaining how the object is balanced.

Newton's 1st Law of Motion

This week, we learned about forces and motions.  One thing I remembered the most from this week's lesson was Newton's 1st Law of Motion.  This law states that "objects in motion [at rest] will tend to stay in motion [at rest] unless acted upon by an outside, unbalanced force".  This weekend I went to support our football boys at their game against Punahou.  When the quarterback threw the ball in the air, it reminded me of the Newton's 1st Law of Motion.  After watching the ball being thrown, seconds later, it landed in another players' hands.  Seeing this, I thought to myself, "Wait a second...objects in motion don't always tend to stay in motion!" Instead of the ball staying in motion in the air forever, it dropped.  Confused, I rethought the situation over.  I then realized my mistake...I had forgotten about the outside, unbalanced force and how it affects objects in motion.  So, it was because of gravity that the ball dropped and eventually stop moving.  Gravity is an example of an outside, unbalanced force mentioned in Newton's 1st Law of Motion.  After the game on Saturday night, I was glad that I was able to incorporate some Physics into the game because I know that when I can relate things to real life situations, I tend to learn better.
...by the way, Congrats on the win Warriors! :)