Física

Andrea Claux
Physics per 1 SL
September 13, 2012

I. TITLE
Investigation of the Flight of Projectile (dart)

II. PURPOSE/OBJECTIVE

The aim of this experiment is to investigate how do changing specific variables affect the kinematics (motion) of the flight of the projectile. This lab will consist of two independent variables and it is important to keep all factors constantthroughout the experiment except for those two. Part A will be investigating how increasing the surface area of the dart affects the velocity of the projectile. Part B will be investigating how increasing the mass of the dart affects the velocity of the projectile.

Part A

Hypothesis: If the surface area of the dart’s head is increased then the velocity will decrease due to the added airresistance limiting the dart to fly faster.

Independent Variable
* Surface Area (calculated by the diameter)
Dependent Variable
* Velocity (calculated by the distance and time)
Controlled Variables
* Angle of launch (45°)
* Dart used
* Dart surface area
* Force

Part B

Hypothesis: If the mass of the dart is increased then the velocity will decrease as well due to therules of gravity; the added mass will cause the dart to land faster.

Independent Variable
* Mass

Dependent Variable
* Velocity (calculated by the distance and time)

Controlled Variables
* Angle of launch (45°)
* Surface Area of dart
* Dart used
* Force

III. MATERIALS LIST:
* Timer
* Measuring tape
* Safety glasses
* Dart launcher
*Protractor
* Duck tape (10 cm)
* Dart (Velcro head)
* 3 Cardboard circle cut outs (1.76 cm, 3.72 cm, 7.41cm in diameter)
* Velcro stickers (3)
* Digital Balance
* Ruler
* Lead shots (9)
* tape

IV. PROCEDURE
Part A
1) Carefully cut out three different sizes of circular pieces of cardboard.
2) Measure each cardboard cutout and record the diameter.
3) Puton safety glasses.
4) Attach the first circular cutout to the head of the dart with the Velcro sticker.
5) Find an open space and use tape to hold your measuring tape flat on the ground.
6) Place the dart inside the launcher.
7) Hold the launcher at a 45˚ angle with help from the protractor.
8) Simultaneously, launch the dart and start the stopwatch.
9) Once landed, stopthe stop watch and measure the distance.
10) Record your data.
11) Repeat steps 6 – 10 to have 3 trials.
12) Change the cardboard cutout for another size and stick it to the head of the dart.
13) Repeat steps 6-11
14) Repeat step 12.
15) Repeat steps 6-11
16) Calculate the surface area of each cardboard cutout using the equation, SA = 4πr2
17) Calculate the velocityof each trial using the equation, V= D/T.
Part B
1) Collect 9 lead shots.
2) Rip 2 pieces of tape about the same size.
3) Attach 3 lead shots to one tape.
4) Attach 6 lead shots to the other tape.
5) Weigh the dart.
6) Record its mass.
7) Weigh the first tape with attached lead shots.
8) Record its mass, and add it to the mass of the dart.
9) Weigh the secondtape with attached lead shots.
10) Record its mass, and add it to the mass of the dart.
11) Put safety glasses on
12) Find an open space and use tape to hold your measuring tape flat on the ground.
13) Place the dart inside the launcher.
14) Hold the launcher at a 45˚ angle with help from the protractor.
15) Simultaneously, launch the dart and start the stopwatch.
16)Once landed, stop the stop watch and measure the distance.
17) Record your data.
18) Repeat steps 13 – 17 to have 3 trials.
19) Attach the piece of tape with 3 lead shots in it to the dart.
20) Repeat steps 13-18.
21) Attach the last piece of tape with 6 lead shots to the dart.
22) Repeat steps 13-18.
23) Calculate the velocity of each trial using the equation, V=...