What's+for+Launch

**The Objective:** Students will Demonstrate an understanding of the terms force, gravity, acceleration, mass, and speed Experiment with the effects of mass on speed and motion Understand that friction and other forces have an effect on motion

 Newton’s Second Law of Motion states that the acceleration of an object depends on the mass of the object and the force applied to it. Since acceleration is a change in velocity with a change in time, both concepts can be explored in relation to Newton’s Second Law. The important fact is that a force will cause a change in velocity; and likewise, a change in velocity will generate a force. We have defined force as equal to mass times acceleration (F=ma), and now we can define acceleration as the force divided by the mass (a=F/m). Greater mass with the same force produces less acceleration and a smaller mass with the same force produces more acceleration. Greater force on the same mass produces more acceleration and less force on the same mass produces less acceleration. Have you ever been at a traffic light, and seen a large truck next to a small car? What happens when they both step on the gas and try to accelerate down the road? Often, the smaller car can accelerate quicker from a stop than a larger truck, as the smaller car has less mass to accelerate. This will cause the smaller car to move ahead of the bigger truck initially. In other words, both the car and the truck can create equal forces even though they are of different masses and moving at different accelerations. If the car (smaller mass) has a high acceleration and the truck (large mass) has a lower acceleration, they may be equal in force. In some ways, that is why a traffic accident can cause a lot of damage even at low speeds as the force exerted by the cars is a product of both the mass and the acceleration of the cars. In space flight there is a fine balance between the total mass of the spacecraft (to include cargo) and the amount of fuel. This ratio is called the mass fraction. More fuel means less cargo, which also means higher orbits can be attained. Larger cargo mass means less fuel and lower orbits. Each mission to space must be carefully weighed (pun intended) prior to liftoff to insure optimal performance of the spacecraft.  __**Terms to Know**__  __**Acceleration**__ Definition:The rate of which an object changes it velocity Context:Acceleration can be positive or negative depending on whether the object is speeding up or slowing down. Definition:A push or a pull exerted on an object Context:The ball was hit with enough force to send it into the bleachers. Definition:A force that resists motion between two bodies in contact Context:Rougher surfaces create more friction than smooth ones when an object comes in contact with them. Definition:The natural force that attracts any two objects with mass toward each other Context:Earth's gravity pulls on anything that is not held up by some other force. Definition:The rate of motion Context:The speed of the ball is determined by measuring how far it travels in a certain amount of time. Definition:The speed of an object moving in a specific direction Context:The car's velocity was 55 miles per hour, eastbound The ratio of fuel mass to spacecraft mass **Check out this site:** []
 * Background:**
 * Where Does This Happen in Real Life?**
 * __Force__**
 * __Friction__**
 * __Gravity__**
 * __Speed__**
 * __Velocity__**
 * __Mass Fraction__**

Data to Collect: Students will use the materials given to them to launch film canisters rockets into inner space. There will three cycles of launches, each with three launches per cycle for a total of nine total. During the first three launches students will test the effectiveness of the spacecraft and fuel by launching a empty spacecraft. Students will carefully mass all componets, fuel and spacecraft, prior to launch to establish the mass fraction (the ratio of fuel mass to spacecraft mass) for an spacecraft without cargo. Students will carefully measure the distance of each launch and tabulate the data on the collection sheet. An average distance will then be noted. During the next two launch cycles additional mass will be added to the spacecraft and the mass fraction will be noted. Again each cycle will consist of three launches and an average distance will be calculated and entered on the data sheets. > 1 gram of aspirin, citric acid, and sodium bicarbonate (NaHCO3) {alka seltzer} Download the student handouts [|2whats for launch data sheet.xls]
 * Materials Needed:**
 * Launch Facility: (1 Inch PVC Pipe) with multiple launch ports.
 * Fuel: 5 mL of H2O (water)
 * Goggles:
 * Measureing tape:
 * Triple Beam Balance
 * Pennies (one cent coins)
 * Tape

Observations: