Rotational and Tangential Velocity:
Tangential velocity is how much distance is covered in a given amount of time. Rotational velocity is the amount of rotations in a given amount of time. A major example of tangential and rotational velocity are gears. 
Which gear will have a larger tangential velocity? Which gear would have a larger rotational velocity. The gears would experience the same tangential velocity, but the smaller gear (gear A) would have a larger rotational velocity because in one rotation made by gear B gear A would have to rotate twice in the same amount of time. So yes to objects could have the same tangential velocities and different rotational velocities.
Explain how the shape of the train wheels keeps the train on the track. Train wheels are shaped the way they are in order to keep them on the track .The irregular shape means that have the same rotational speeds and different tangential speeds. This is because when on a turn the wider part of the wheel is moving faster than the thinner part of the wheel on the other side of the track which means this over compensation of movement re-aligns the wheels onto the track.
merry- go- round
Rotational Inertia and Conservation of angular momentum:
Which would win a race: the solid ball or the hoop? The solid ball would win a race down an inclined plane over a hoop because its mass is closer to its axis of rotation which means its easier for the mass to move as a unit in one direction than the hoop which rotates less times in the same amount of time, thus traveling a shorter distance and the solid ball winning.
Common Life Example:
Angular momentum characterizes an object's resistance to change in rotation. The basic idea is the same as with linear momentum: moving things like to keep moving, and to change their motion we have to apply a force. If no force is present, then momentum doesn't change. In the case of rotation, the force is called torque. A spinning figure skater has a nearly friction less contact with the ice, and there is little net torque on her body. Her angular momentum is nearly conserved.The figure skater moves faster when her arms are closer to herself because her mass is closer to her center of mass, which is the same as the solid ball. The image of the figure skater with her arms out compares to the movement of the hoop in the example above.
Conservation of angular momentum is a measure of the amount of rotation an object has. It is a vector quantity that represents the product of a body's rotational inertia and rotational velocity about a particular axis.
Angular moment= rotational inertia * rotational velocity
Angular momentum before= Angular momentum after
rotational inertia * rotational velocity (before)= rotational inertia * rotational velocity (after)
RI * rotational velocity= RI * Rotational velocity
Torque and Center of Mass/ Gravity:
Torque causes rotation. Torque= force* lever arm
Where is the best place to put a door stop?
The best place to put a door stop is farther from the hinge because it increases the torque on the door. The torque is increase because the lever arm which is the perpendicular distance from the axis of rotation to the line of rotation to the line of action of the force has increased. Torque can also be increased if the force is increased (which in this case cannot be changed) or both the force and lever arm are increased.
Common Life Examples:
Why do we lean forward when we wear backpacks? We lean forward when we wear backpacks in order to push our center of gravity forward. This is because the weight of the backpack is heavy therefore it pushes our mass out of our base of support by leaning forward we put our center of mass within our base of support.
The lady will fall over if pushed rather than the man who stands in an athletic position ( knees bent and feet shoulder width apart). When we widen our base of support (which is what the man is doing) and lower our center of mass we make it harder for someone to move us because our center of mass is over a larger base of support.
A common example today is the Leaning Tower of Pisa which looks like it'll fall over, but it won't because its center of gravity (as shown) is within its base of support.
Why did Thor fall?
Centripetal and Centrifugal Forces:
Centrifugal force is the apparent force that draws a rotating body away from the center of rotation.
Centrifugal force is a "fictitious" force.
Centripetal force is a force that makes a body follow a curved path toward the fixed point of the instantaneous center of curvature of the path. Centripetal force is generally the cause of circular motion.
Common Life Example:
A major example of centripetal force is found on roller coaster turns. Why do clothes get drier in the spin cycle of the washing machine?
The clothes in a spin cycle of a washing machine are trying to go straight but because of the centripetal force on the drum of the washing machine they follow a curved path thus moving wit the movement of the drum. The water because it's not affects by the centripetal force of the machine moves freely throughout the drum and eventually exit through the holes in the drum to an external drum.
Reflection:
WHAT I FOUND MOST DIFFICULT ABOUT THIS UNITI found centripetal force the most difficult in this unit. I experienced troubles with the race car track elevation concept and the roller coaster concept. However, by speaking to my teacher after many seated meals I was able to overcome my frustration and just speak about physics in a way that I could understand. The light bulb clicked during this unit for me, I was able to sit down and just understand what we've already knew in a more scientific way.
Problem Solving Skills Last semester, I tried very hard to problem solve well in science but never fully understood so that I may do so. However, this semester I have payed attention more and took it to the next level by going to my teacher. I complete my homework as thoroughly as possible instead of just trying to get it over with. With a little more work on grasping the whole picture I could see my problem solving skills are definitely improving.
Reflection:
WHAT I FOUND MOST DIFFICULT ABOUT THIS UNITI found centripetal force the most difficult in this unit. I experienced troubles with the race car track elevation concept and the roller coaster concept. However, by speaking to my teacher after many seated meals I was able to overcome my frustration and just speak about physics in a way that I could understand. The light bulb clicked during this unit for me, I was able to sit down and just understand what we've already knew in a more scientific way.
Problem Solving Skills Last semester, I tried very hard to problem solve well in science but never fully understood so that I may do so. However, this semester I have payed attention more and took it to the next level by going to my teacher. I complete my homework as thoroughly as possible instead of just trying to get it over with. With a little more work on grasping the whole picture I could see my problem solving skills are definitely improving.
