Week of December 14, 2009

This week during Science I learned more about forces. i learned that the earth applies more force on a heavier object, but when you drop the two they hit the ground at the same time. We also talked more about the greater the force that you have the greater the acceleration of an object. And the less the mass the greater the acceleration. I also learned that when two forces are balanced, there is no acceleration. The object is either not moving or moving at a steady rate. An object is always moving at a steady rate, even if it is a steady rate of 0 miles per hour or meters per second. We also talked a lot about friction and what a world without friction would be like. You would not be able to stop driving or to stop sliding unless you crashed. You would not even be able to start running because in order to start you have to use friction to push your feet off the ground. We learned about Newton's Third Law. When Kathy pushed on Laura and they were on carts, Laura and Kathy both moved. We also tested this on springs. What we learned from this was that even if an object is not pushing back, it is pushing back and that every object returns the same amount of force that is pushed against it.

I learned this by doing the spring experiment, the Laura and Kathy experiment, and dropping two thing while standing on a counter.

It is important to know these things because if you do not know Newton's three laws then you will not understand how an object starts to move, how it keeps moving, and how other objects effect the way he moves.

Week of December 7, 2009

This week in Science i continued learning about forces and their effect on the objects in the world around them.

Thing Learned: drawing force diagrams

Learned By: identifying all of the forces that effect an object of interest and the direction that they are pushing

Thing Learned: which way an object of interest will move

Learned By: identifying the unbalanced force effecting the object and which way it is pushing

TL: that delta V arrows and the direction of the object (like a ball or car) go in the same direction

LB: drawing force diagrams and comparing them to the delta V arrows on motion diagrams when they are drawn

TL: that two balanced forces cancel each other out and make the object of interest stay still

LB: splitting into two equal groups and pushing on opposite sides of Mr. Finley's car

TL: scales measure the force of someone/something applied on them (weight not mass)

LB: watching Amy and Amanda do an experiment on You-Tube

TL: people weigh less on the earth's moon (or other small planets or moons) than they do on earth

LB: comparing the earth's mass to the mass of other planets because the mass of the earth is bigger so the pull of the earth is stronger

TL: the greater the mass the smaller the acceleration

LB: having Kathy and Laura pull Mark, JR, and Aage in a cart

It is important to know these things if you go into physics in college or high school and also so you can just understand who will go faster down a slide; you or your little brother, and so you will understand that you don't actually get fatter in an elevator.

Week of 11/30/09

This week in science I learned about forces and their effect compared to other forces. Like the force of your hand against the forces of gravity. I learned how to make force diagrams. You make a dot and label it the object of interest. like a ball or house or frame. Then you draw all of the forces that effect the object as arrows. The longer the arrow, the stronger the force. You label the arrows the F (force) of an object on the object of interest. I also learned that all objects and only objects can exert force.

I learned these things by having one person hold two thing in their hands, like a bowling ball and a basketball, and ask them if they are exerting more force to one of the objects. I learned about the forces by drawing pictures of the situation that is in the question. Then you draw arrows on the picture to explain the forces. I learned what length to make the arrows by knowing that if the two arrows are equal and the equation equals zero that the object is being held steady.

It is important to know these things because forces are all around us and so we should know what a force is and how they work. We also should know about which things exert forces so we can predict how an experiment is going to work. Also, if you will eventually be taking physics then you should know all about forces and how they effect the objects around them. Forces are everywhere, so you should know about them and how to factor them into a situation. That is why you should know how to draw a force diagram.