CO2 Dragster Project

About this Module

You will convert a wedged shape piece of wood (about 12” in length) into a sleek racecar body using hand or power tools. Paint, wheels are added to make the car race worthy.

The cars speed down the track and cross the finish line in speeds less than one second.

About the Module Continued

You will follow guidelines or restrictions that are outlined in the booklets provided.

Students will use a Design Process to follow when building their CO2 Dragster.

CO2 Powered DragsterWHAT DO WE USE TO POWER OUR DRAGSTER?

Compressed C02 – Carbon Dioxide

Carbon Dioxide

Inorganic compound, a colorless gas with a faint, sharp odor and a sour taste when dissolved in water, chemical formula CO2.

About 0.03% of air by volume, it is produced when carbon-containing materials burn completely and from fermentation and animal respiration. Plants use CO2 in photosynthesis to make carbohydrates.

Carbon Dioxide

Under pressure it becomes a liquid, the form most used in industry.

If the liquid is allowed to expand, it cools and partially freezes to the solid form, dry ice.

It is used as a refrigerant, chemical intermediate, and inert atmosphere; in fire extinguishers, foaming rubber and plastics, carbonated beverages

Force

Force is simply a push or a pull.

When F = 0 an object at rest will stay at rest or an object in motion will stay in motion.

When F > 0 an object will accelerate(a) in ratio to the objects mass(m). F = m x a

Mass

Mass is the amount of matter in an object. It has no direction associated with it. Mass stays the same no matter what force

is acting on the object. Weight is the force of the earth's gravity

that is acting on object’s mass.

Weight = Mass x Gravity

Acceleration Acceleration is simply the increase of speed or velocity of an

object. If an object is not changing its velocity than it is not

accelerating.

What are some examples of something that is accelerating in speed?

                                               

Kinetic Energy

Kinetic energy is the energy of motion. An object which has motion - whether it be vertical or horizontal motion - has kinetic energy.

Like work and potential energy, the standard metric units of measurement for kinetic energy is the Joule.

Potential Energy

An object can store energy as the result of its position. For example, the heavy ram of a pile driver is storing energy when it is held at an elevated position. This stored energy of position is referred to as potential energy.

PE = mgh

PE = Energy (in Joules) m = mass (in kilograms) g = gravitational acceleration of the earth (9.8 m/sec2) h = height above earth's surface (in meters)

Sources of Energy that Fuel Real World Technologies Internal Combustion Engine

Steam Engine

Rocket Engine

Mechanical Energy

Electric Motor

Gas turbine

Internal Combustion Engine

Steam Engine

Rocket Engine

Mechanical Energy

Electric Motor

Gas Turbine

Kinetic Energy = ½ MV2

If a CO2 dragster with a mass of 1 kilogram is moving at 15 meters per second what is its kinetic energy?

Force = Mass x Acceleration

If a CO2 dragster with a mass of 1 kilogram is accelerating 20 meters per second what is the force being provided by the CO2 cartridge?

Newton’s Laws

1st law-If an object is at rest, it tends to stay at rest, and if an object is in motion, it tends to stay in motion at a constant velocity until an outside force affects the object's state of inertia.

Also known as law of inertia

Newton’s 2nd Law

If an unbalanced force acts on an object, the object accelerates in the direction of the force. The acceleration varies directly with the unbalanced force. The acceleration varies inversely with the mass of the object.

F = ma

Newton’s 3rd Law

for every action force, there exists a reaction force that is equal in magnitude but opposite in direction

Newton's third law states that for every action force there is an opposite and equal reaction force.

Goal – The most efficient dragster

Efficiency is the relationship between energy input and energy output.

Efficiency is expressed as a percentage. The more efficient a system, the less energy that is lost within that system.

What causes your dragster to lose of energy?

Drag Friction Excess Mass

Drag

When the CO2 dragster travels down the track, its frontal area pushes against the air in front of it, and air flowing over the body causes friction. This is known as drag.

How do we reduce drag?

Friction

Friction is a force that is created whenever two surfaces move or try to move across each other.

Friction always opposes the motion or attempted motion of one surface across another surface. How do we reduce friction?

Excess Mass

The more mass a dragster has, the slower the acceleration.

The force will be the same for all dragsters. It is provided by the CO2 cartridge.

How do we reduce mass?

Dragster Design Process

1) Clarify the problem

2) Research and investigate

3)Generate design

4) Choose a solution

5) Develop a prototype

6) Test and evaluate

7) Redesign the solution

Vocabulary

Carbon Dioxide Force Mass Weight Acceleration Velocity Kinetic Energy Potential Energy

Refrigerant Internal

Combustion Engine

Physics Efficiency Drag Friction Inertia