Analysis Questions A-E

A.) Newton’s first law of motion explains why the car started moving and why the car came to a stop. Newton’s first law of motion states that an object at rest will remain at rest and an object that is moving at a constant velocity will continue moving at a constant velocity unless acted upon by an unbalanced force. When the Balloon Car started to roll, the air inside the balloon came in contact with the air on the outside. The air inside of the balloon pushed out against the air on the outside causing the balloon car to accelerate. About 40 seconds later the balloon car stopped. It stopped because the balloon had no more air to push against the air on the outside. Therefore the air inside the balloon and the outside air would be considered unbalanced. Newton’s first law of motion proves that once the car comes in contact with another force that is unbalanced, the car will move, but once the air inside of the car is gone, the air on the outside won’t have to fight with another force causing the car to come to a complete stop.

B.) Newton's second law of motion explains how the mass of my balloon car affected the acceleration as the balloon car just started going. Newton's second law of motion states that the force of an object is equal to the product of its mass and acceleration, which is displayed by the equation F=ma. This law implies that the equations m=F/a and a=F/m are also true. When mass is increased and force stays the same, then acceleration will decrease, so acceleration and mass are inversely proportional. This information is incredibly important considering the force applied on the balloon car will always be the same because the 12" balloon is the only force applied. While creating the balloon car, the only factor that we needed to question from the second law is mass. The group had to make sure that the mass was less so that the acceleration would be greater. Newton's second law explains that if my balloon car has a lower mass, then the acceleration will be greater.

C.)

Momentum, the product of the mass and velocity of an object, is present in the balloon car project. The mass of the balloon car affects how fast the balloon car goes because the more mass the more momentum there is. This makes mass and momentum directly proportional. The velocity of the balloon car also affects the momentum. The faster an object is going the more momentum it has, therefore also making velocity and momentum directly proportional. The balloon car continued to move after the air had blown out of the balloon because the air had given the car momentum to keep on moving. The air in the balloon had pushed out of the balloon which caused the balloon to push on the air. This made the car accelerate forward. The velocity of the car slowly decreased because of the friction of the air and the ground, causing the momentum to slowly decrease. Mass and velocity affected the balloon car’s ability to keep moving through the hallway.

D.)

Newton’s third law of motion, which states that every action has an equal and opposite reaction, is applied in the balloon car project. This law is applied firstly by the air being pushed into the balloon when it was blown up. The air on the inside was exerting a force on the air on the balloon, while the balloon exerted an equal force on the air. The first object in this pair of action and reaction forces is the air, while the second object is the balloon. Another time when the balloon car represented Newton’s third law of motion was when the first object, the wheels of the car, pushed against the ground, causing the reaction force of the ground, the second object, to push against the wheels. This caused the car to move forward and accelerate across the floor of the hallway in which it was tested in. The force in the third law of motion relates to the first law of motion because the force of the car moving would just keep moving unless there had been another force to stop it. The balloon car was stopped by the friction of the floor against the wheels and the friction of the air on the car. Newton’s third law of motion is demonstrated multiple times in the balloon car project.

E.) All three types of friction affect the motion of the balloon car, so the car is designed to allow the most motion possible. Friction is the force that one surface exerts on another in the opposite direction that the object is going when the objects rub against each other. Friction will slow the balloon car down to a stop, and will slow the car down faster if the friction is stronger. The strength of friction is dependent on the types of surfaces involved and how hard the surfaces push together. There are three types of friction: sliding, rolling, and fluid. Sliding friction is the strongest friction and is caused when one object slides across a surface. Sliding friction is the strongest because there is most likely more surface area involved, meaning there is more space where friction can be created. During the design process, my group made sure there was as little sliding friction as possible. To do this, we just made sure nothing touched the ground other than the wheels. This is important because nothing important to the function of the car needs to touch the ground, so we want to make sure that this especially does not impede our cars motion. Rolling friction is the second strongest friction and is caused when one object rolls on another. There is less friction involved in rolling friction because there is less surface area for the object to come in contact with. Rolling friction is required in a car's motion, but the type of wheel that is on the car can determine how much friction will be involved. During the design process of the car, our group chose to use a CD for the wheels because a CD is thin and smooth, which means that only a small amount of surface area touches the ground. Fluid friction is the weakest friction and is caused when a fluid, a gas or liquid, rubs against a surface. Fluid friction is the least strong friction because it keeps objects from touching one another. The type of fluid friction that will affect the car is air resistance. Air resistance is affected by the area of the car, so the bigger the area, the stronger the air resistance. While designing the balloon car, we made sure that the car allowed as much air pass through it as possible, so we used an egg carton. The egg carton was small, smooth, and let air pass through it easily. Overall, friction slows the balloon car down, so the design of the car has to make the friction as weak as possible. The three types of friction each impede the acceleration of my balloon car, so the car is designed so that the friction is weak.