**TITLE “The
Firing Squad”** (ACADEMIC)

**BACKGROUND A common use of
projectiles in motion is in some sort of weapon. By analyzing the behavior of
the motion of a projectile, such as a dart gun, you can use it to make
predictions about how projectiles work.**

**TASK Design
and conduct experiments to determine the location and angle at which to stand,
along with your classmates in a circle, in order to fire a nerf dart gun so it
exactly hits your physics teacher on the top of the head.**

**AUDIENCE: Teacher and peers**

**PURPOSE: To use and apply
knowledge of projectiles in motion.**

**PROCEDURE:**

**Obtain Materials: nerf dart gun
(use the same gun and dart each time) , meter stick, measuring tape, calculator,
graph paper, masking tape.**

**I) Keeping the gun perfectly horizontal, so its initial vertical
(y) velocity is zero, devise a method for accurately determining the “muzzle”
velocity of the gun. (You can determine the Dx and Dy) **

h

Dx

H=1/2gT^{2}. solve for T Vx=Dx/T

Also calculate the projectile’s acceleration in the gun.

** Conduct
your experiment, including several trials and the effects of air resistance.**

** **

** 2. Using your
results, practice by determining angle and range to a target several meters
away. Keep track of your results.** Place a
target 1-5 meters away about 2 meters off the ground. Holding the dart at
about .5 meters off the ground, at
different angles (20, 40, 50, 60?) calculate using your previous results (so
now =Vx), the exact distance away at which you must hold the gun
in order to hit the target (on the way up and/or on the way down).

** **

** Graph
your results, dependent on height, angle, and range to target.**

**Present your results to the
class.**

**3. Using your formula, calculate
how to aim to hit the teacher with the rest of the class.**

Holding the gun at a 45 degree
angle, calculate where you should stand to directly hit the top of my head as I
am seated. (Dy=0, V = muzzle velocity of gun)

**Record and analyze your results!**

Take out
“Firing Squad” Info.

Find
“your” dart gun. Make sure you know its velocity.

(You did
this by firing horizontally at a certain distance…..

V = Dx/T where
T= sqrt ( 2 Dy / Ay ) where Dy is the distance it dropped. )

----------------------------

Immediately
calculate Part Three….. Firing at my head with a Dy of 0, angle of 45 degrees.

Dx
= 2V^{2}/Ay * sin (45)*cos (45)

Test it
out!

Make sure you have a table for each part
with measurements and calculations:

I)

Dx (you
decide)| Angle(zero!) | Dy (you measure) | T (you calculate) | Vx (you
calculate)

II)

Test your
gun at different angles, height of target, and distance away and see if physics
works!

Show your
actual data, and what it should’ve been

Dy (you
decide)| Angle(you decide)|V (you know) |T (you calculate) | Dx (you calculate)

**Honors

Dy (you
decide)| Dx (you decide) |V (you know) |T (you calculate) |Angle(you
calculate)|

III)

Dy (0)|
Angle(45)|V (you know) |T (you calculate) | Dx (you calculate)

---------------------------------------------------------------

In your
conclusion:

What
forces were acting on the dart at each point of its journey?

In the
Gun? On the way up? On
the way down? When it hit?
After?

What do
you think those forces depend on? (How could they change?)

How did
the force affect the motion of the dart?

------------------------

By
the end of class: Have all your measurements…. THEN make sure your data is in a
clear table, THEN finish writing your conclusions.

**Performance
Task Assessment List**

**TITLE: THE FIRING SQUAD**

A. PHYSICS

__ Assessment
Points __

Points __Earned
Assessment:__

__Element____
Possible Self____ ____ Teacher__

**PLANNING**

- Outline
of experiment purpose 5

_______________________________________________________________________

- Procedure
to determine muzzle velocity 15

_______________________________________________________________________

- Data
on muzzle velocity (including spring/air resistance) 10

_______________________________________________________________________

- Explanation
of muzzle velocity results 10

_______________________________________________________________________

- Overall
calculation of range/angle/height for gun 10

_______________________________________________________________________

- Presentation
of results with graph and formulas 10

_______________________________________________________________________

- Presentation
to class, clear, well thought out. 10

_______________________________________________________________________

- Trial
run with target 5

_______________________________________________________________________

- Final
results of firing squad 5

_______________________________________________________________________

- Discussion of validity,error analysis

and conclusions for further study 10

_______________________________________________________________________

**TOTAL __90___ _____ _____**

** **

**TITLE “The
Firing Squad”** (HONORS)

**BACKGROUND A common use of
projectiles in motion is in some sort of weapon. By analyzing the behavior of
the motion of a projectile, such as a dart gun, you can use it to make
predictions about how projectiles work.**

**TASK Design
and conduct experiments to determine the location and angle at which to stand,
along with your classmates in a circle, in order to fire a nerf dart gun so it
exactly hits your physics teacher on the top of the head.**

**AUDIENCE: Teacher and peers**

**PURPOSE: To use and apply
knowledge of projectiles in motion.**

**PROCEDURE:**

**Obtain Materials: nerf dart gun
(use the same gun and dart each time) , meter stick, measuring tape, calculator,
graph paper, masking tape.**

**I) Keeping the gun perfectly horizontal, so its initial vertical
(y) velocity is zero, devise a method for accurately determining the “muzzle”
velocity of the gun. (You can determine the Dx and Dy) **

h

Dx

H=1/2gT^{2}. solve for T Vx=Dx/T

Also calculate the projectile’s acceleration in the gun.

** Conduct
your experiment, including several trials and the effects of air resistance.**

** 2. Using your results, practice by
determining angle and range to a target several meters away. Keep track of your
results.** Place a target 1-5 meters away
about 2 meters off the ground. Holding the dart at about .5 meters off the ground, at different
angles (20, 40, 50, 60?) calculate using your previous results (so now =Vx), the exact distance away at which you must hold the gun
in order to hit the target (on the way up and/or on the way down).

**Also
find the correct angle to hold the gun so it hits the target on the way down 2
meters away, 2 meters off the ground.**

** **

** Graph
your results, dependent on height, angle, and range to target.**

**Present your results to the
class.**

**3. Using your formula, calculate
how to aim to hit the teacher with the rest of the class.**

Holding the gun at an angle,
calculate where you should stand to directly hit the top of my head as I am
seated. (Dy=0, V = muzzle velocity of gun)**Record and analyze your results!**

Take out
“Firing Squad” Info.

Find
“your” dart gun. Make sure you know its velocity.

(You did
this by firing horizontally at a certain distance…..

V = Dx/T where
T= sqrt ( 2 Dy / Ay ) where Dy is the distance it dropped. )

----------------------------

Immediately
calculate Part Three….. Firing at my head with a Dy of 0, angle of 45 degrees.

Dx
= 2V^{2}/Ay * sin (45)*cos (45)

Test it
out!

Make sure you have a table for each part
with measurements and calculations:

I)

Dx (you
decide)| Angle(zero!) | Dy (you measure) | T (you calculate) | Vx (you
calculate)

II)

Test your
gun at different angles, height of target, and distance away and see if physics
works!

Show your
actual data, and what it should’ve been

Dy (you
decide)| Angle(you decide)|V (you know) |T (you calculate) | Dx (you calculate)

**Honors

Dy (you
decide)| Dx (you decide) |V (you know) |T (you calculate) |Angle(you
calculate)|

III)

Dy (0)|
Angle(45)|V (you know) |T (you calculate) | Dx (you calculate)

---------------------------------------------------------------

In your
conclusion:

What
forces were acting on the dart at each point of its journey?

In the
Gun? On the way up? On
the way down? When it hit?
After?

What do
you think those forces depend on? (How could they change?)

How did
the force affect the motion of the dart?

------------------------

By
the end of class: Have all your measurements…. THEN make sure your data is in a
clear table, THEN finish writing your conclusions.

**Performance
Task Assessment List**

**TITLE: THE FIRING SQUAD**

H. PHYSICS

__ Assessment
Points __

Points __Earned
Assessment:__

__Element____
Possible Self____ ____ Teacher__

Outline of experiment purpose 5

_______________________________________________________________________

Procedure to determine muzzle velocity 15

_______________________________________________________________________

Data on muzzle velocity (including spring/air resistance) 10

_______________________________________________________________________

Explanation of muzzle velocity results 10

_______________________________________________________________________

Overall calculation of range/angle/height for gun 10

_______________________________________________________________________

Presentation of results with graph and formulas 10

_______________________________________________________________________

Presentation to class, clear, well thought out. 10

_______________________________________________________________________

Trial run with target 5

_______________________________________________________________________

Final results of firing squad 5

_______________________________________________________________________

Discussion of validity,error analysis

and conclusions for further study 10

_______________________________________________________________________

**TOTAL __90___ _____ _____**

** **

** **

** **