I chose this video because it show a hands on experiment being done on the project which makes it easier to understand. He also shows us using many tools for us to see for ourselves opposed to just listening and believing him based off what we hear.
Friday, February 14, 2014
Friday, January 31, 2014
Unit 4 Blog Reflection
I. Rotational and Tangential Velocities
I. Rotational Velocity: Number of times you rotate per unit of time (Angular Speed)
Tangential Velocity: The speed of something moving around a circular path
Linear Velocity: The same as Tangential Speed
Less rotational inertia=easier to spin
This Unit told us that the center of a rotating circle moves slower than the outer parts of that circle. This is because they are rotation with the same rotational velocity, however, once you look on the outside which is much larger than the inside, you have to wander how it stays balanced or keeps up with the inside. It has more ground to cover therefore it goes faster.
II. Rotational Inertia: It is the property of an object to resist changes in spin
Lots of rotational inertia = harder to spin
A little rotational Inertia = easier to spin
Who is spinning faster, the one at the left or the one at the right?
Well the one on the left is because she is decreasing her rotational inertia by bringing her arms in which makes her rotate much faster than the one on the left who has her arms out.
Conservation of angular momentum means:
total momentum before = same momentum after
R.I. x R.V. before = R.I. x R.V. after
So if I have a.... R.I. x r.v. = r.i. x R.V.
angular momentum = rotational inertia x rotational velocity
III. Torque: something that causes rotation
Torque = Force x Lever arm ( where the lever arm is the distance from the axis of rotation)
The bigger the lever arm the less force it takes to put into an object
IV. Center of Mass: the average position of an objects mass
Center of Gravity: when gravity acts on the center of mass
This is why in football we bend our legs because one, we lower our center of gravity which makes it harder for us to fall over and two other players are bending their legs, but whoever gets their center of gravity the lowest, they will run over their opponents.
V. Centripetal/Centrifugal Force
Centripetal force is the force that helps us turn. It does this by pulling us inward while we are wanting to go outward.
This unit seemed to be very interesting to me. Although I did reach my goal of understanding the material alot better and actually paying attention in class, I feel that I need to do that alot often. As seen in the torque lab, I found the meter stick problem really challenging, however after constantly practicing it, I feel that I have mastered that concept. Physics is seen in everyday life, and more specifically, rotation is seen in everyday life, so this helped me understand something from real life.
II. Rotational Inertia/Conservation of Angular Momentum
III. Torque
IV. Center of Mass/Gravity
V. Centripetal/Centrifugal Force
Tangential Velocity: The speed of something moving around a circular path
Linear Velocity: The same as Tangential Speed
Less rotational inertia=easier to spinThis Unit told us that the center of a rotating circle moves slower than the outer parts of that circle. This is because they are rotation with the same rotational velocity, however, once you look on the outside which is much larger than the inside, you have to wander how it stays balanced or keeps up with the inside. It has more ground to cover therefore it goes faster.
II. Rotational Inertia: It is the property of an object to resist changes in spin
Lots of rotational inertia = harder to spin
A little rotational Inertia = easier to spin
Who is spinning faster, the one at the left or the one at the right?
Well the one on the left is because she is decreasing her rotational inertia by bringing her arms in which makes her rotate much faster than the one on the left who has her arms out.
Conservation of angular momentum means:
total momentum before = same momentum after
R.I. x R.V. before = R.I. x R.V. after
So if I have a.... R.I. x r.v. = r.i. x R.V.
angular momentum = rotational inertia x rotational velocity
III. Torque: something that causes rotation
Torque = Force x Lever arm ( where the lever arm is the distance from the axis of rotation)
The bigger the lever arm the less force it takes to put into an object
IV. Center of Mass: the average position of an objects mass
Center of Gravity: when gravity acts on the center of mass
This is why in football we bend our legs because one, we lower our center of gravity which makes it harder for us to fall over and two other players are bending their legs, but whoever gets their center of gravity the lowest, they will run over their opponents.
V. Centripetal/Centrifugal Force
Centripetal force is the force that helps us turn. It does this by pulling us inward while we are wanting to go outward.
This unit seemed to be very interesting to me. Although I did reach my goal of understanding the material alot better and actually paying attention in class, I feel that I need to do that alot often. As seen in the torque lab, I found the meter stick problem really challenging, however after constantly practicing it, I feel that I have mastered that concept. Physics is seen in everyday life, and more specifically, rotation is seen in everyday life, so this helped me understand something from real life.
Wednesday, January 29, 2014
The Meter Stick Lab
Our goal for the meter stick lab was to find the weight of the meter stick without weighing it, but instead using a table, an 100g weight, and the meter stick itself. The formulas that we will need to use in order to solve this problem are: w = m*g
lever arm * F = lever arm * F (counter-clockwise torque = clockwise torque)
To start this project, we had to find the center point of the meter stick as it balances on the table. Luckily, it balanced directly at the halfway mark which was 50 cm. Next you must add the 100g weight to the end of the meter stick, and immediately, we see that the meter stick drops off the table. Why is this? It's simply because it isn't balanced. In order for it to balance out, you would have to slide the meter stick creating what we scientifically would call a lever arm in order to find the torque of the object.
This is an example of what the new lab would look like. Seeing this, we can add the formula for torque which is: Lever Arm 1= 30 Lever Arm 2 = 20
counter-clockwise torque = clockwise torque
(lever arm)(F) = (lever arm)(F)
(30)(.98) = (20)(F)
29.4 = (20)(F)
20 20
1.47N = F
W = (M)(G)
1.47N = (M)(9.8)
9.8 9.8
.15Kg = M
150g = M
(Actual mass was 150.8)
lever arm * F = lever arm * F (counter-clockwise torque = clockwise torque)
To start this project, we had to find the center point of the meter stick as it balances on the table. Luckily, it balanced directly at the halfway mark which was 50 cm. Next you must add the 100g weight to the end of the meter stick, and immediately, we see that the meter stick drops off the table. Why is this? It's simply because it isn't balanced. In order for it to balance out, you would have to slide the meter stick creating what we scientifically would call a lever arm in order to find the torque of the object.
This is an example of what the new lab would look like. Seeing this, we can add the formula for torque which is: Lever Arm 1= 30 Lever Arm 2 = 20
counter-clockwise torque = clockwise torque
(lever arm)(F) = (lever arm)(F)
(30)(.98) = (20)(F)
29.4 = (20)(F)
20 20
1.47N = F
W = (M)(G)
1.47N = (M)(9.8)
9.8 9.8
.15Kg = M
150g = M
(Actual mass was 150.8)
Monday, January 20, 2014
Monday, January 13, 2014
Rotational Inertia
I chose this video because it shows us through a hands on demonstration the way that Rotational Inertia works. This video is short, sweet, and gets to the point.
Friday, November 1, 2013
Unit 2 Blog Reflection
Newton's 2nd Law
Newton's second law stated that acceleration is directly proportional to force and inversely proportional to mass. In simpler terms, this basically means that as the acceleration goes up the force will increase as well and the mass will decrease however if the acceleration decreases the mass is increased. In formula form, it is written as a = F/M, where F is the force and M is the mass.
Another part of Newton's Second Law was the fact that mass and weight are not equal. In order to find the mass of and object you simply divide the weight by 9.8 (rounded to 10) or to find the weight of something you multiply the mass by 9.8 (rounded to 10). A simple formula to remember for this process is W=GM. Where the W is representing your weight, the G which stands for gravity is the 9.8 (rounded to 10) you multiply or divide with, and the M is your mass.
Sky Diving
In our sky diving lesson, we learned immediately that the speed that an object travels in the air effects your air resistance in a manner that is very similar. In fact a persons speed and air resistance are directly proportional to one another. This will happen until the object that is in the air reaches a terminal velocity (constant speed). In this picture, we see a picture of a man sky diving. In the (a) step, we see he is jumping out of the plane from rest so his force is only 980N, which looks sort of like 9.8 (force of gravity). As he is falling he begins to accelerate because as we stated earlier in Newton's Second Law, force is directly proportional to acceleration. In step (c), he is still increasing acceleration and his velocity and acceleration are all going downward. However, in the (d) step, when he opens up his parachute, his velocity is still going downward, but his acceleration is now going upward. Don't let this confuse you though. All this means is that he is beginning to slow down. He is going to continue to slow down until he slowly reaches terminal velocity again. With more air resistance now hitting the man due to the parachute, his speed steadily drops.
Free Falling
In free fall, their is absolutely no air resistance, there for gravity is the only force action on any falling object. Knowing this, we know that the weight of an object no longer matters, because gravity is the only force pushing on the object which gives us 9.8 (rounded to 10). So if you were to drop two things from an equal height in free fall, whether a feather and a coin or two balls of different mass, they will hit the ground at the same time.
Throwing Things Up
This is a video that my group made about throwing things up in the air. Just remember this is how you would typically solve for one of these problems.
Projectile Motion
In projectile motion, there are two terms you need to know:
My Problem Solving Skills and etc...
This was a tougher unit for me because it was alot of things you had to know to fully understand Newton's first law. Saying this, I tended to get frustrated alot, even in group project I started to shut down when I didn't understand a problem, however now i understand it due to the several labs that we did in this unit. The videos that I watched on my own also helped me alot. My goal for next time is to never give up, even when the work load seems to get intense, I have to continue to work at it and ask several questions.
Newton's second law stated that acceleration is directly proportional to force and inversely proportional to mass. In simpler terms, this basically means that as the acceleration goes up the force will increase as well and the mass will decrease however if the acceleration decreases the mass is increased. In formula form, it is written as a = F/M, where F is the force and M is the mass.Another part of Newton's Second Law was the fact that mass and weight are not equal. In order to find the mass of and object you simply divide the weight by 9.8 (rounded to 10) or to find the weight of something you multiply the mass by 9.8 (rounded to 10). A simple formula to remember for this process is W=GM. Where the W is representing your weight, the G which stands for gravity is the 9.8 (rounded to 10) you multiply or divide with, and the M is your mass.
Sky Diving
In our sky diving lesson, we learned immediately that the speed that an object travels in the air effects your air resistance in a manner that is very similar. In fact a persons speed and air resistance are directly proportional to one another. This will happen until the object that is in the air reaches a terminal velocity (constant speed). In this picture, we see a picture of a man sky diving. In the (a) step, we see he is jumping out of the plane from rest so his force is only 980N, which looks sort of like 9.8 (force of gravity). As he is falling he begins to accelerate because as we stated earlier in Newton's Second Law, force is directly proportional to acceleration. In step (c), he is still increasing acceleration and his velocity and acceleration are all going downward. However, in the (d) step, when he opens up his parachute, his velocity is still going downward, but his acceleration is now going upward. Don't let this confuse you though. All this means is that he is beginning to slow down. He is going to continue to slow down until he slowly reaches terminal velocity again. With more air resistance now hitting the man due to the parachute, his speed steadily drops.Free Falling
In free fall, their is absolutely no air resistance, there for gravity is the only force action on any falling object. Knowing this, we know that the weight of an object no longer matters, because gravity is the only force pushing on the object which gives us 9.8 (rounded to 10). So if you were to drop two things from an equal height in free fall, whether a feather and a coin or two balls of different mass, they will hit the ground at the same time.
Throwing Things Up
This is a video that my group made about throwing things up in the air. Just remember this is how you would typically solve for one of these problems.Projectile Motion
In projectile motion, there are two terms you need to know:
- Vertical Distance: has a constant acceleration (10m/s^2). We use the formula d=1/2gt^2. Vertical velocity is basically the height, and the height determines time.
- Horizontal Distance: always remains with a constant velocity because it has no force. We can calculate horizontal velocity by using the formula v=d/t
My Problem Solving Skills and etc...
This was a tougher unit for me because it was alot of things you had to know to fully understand Newton's first law. Saying this, I tended to get frustrated alot, even in group project I started to shut down when I didn't understand a problem, however now i understand it due to the several labs that we did in this unit. The videos that I watched on my own also helped me alot. My goal for next time is to never give up, even when the work load seems to get intense, I have to continue to work at it and ask several questions.
Thursday, October 24, 2013
Free Fall
In this video it describes what free fall is and like in all my other videos, I chose this video in order to relate it back to things we do in every day life. Not that we go to the fair everyday but we have seen or either rode this ride before. He does a great job explaining how this ride is under free fall.
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