DSHS Physics Mathy Chapter 3 Projectiles Name:
Partner: Date:
Lab #5 Nerf Projectiles
R=
vi 2 Sin2θ
g
Now that we are familiar with the derivative
we will put it to use in a practical manner. The goal is to use
only the tiles in the entry hall ( 1 ft each) and a stopwatch, and from these two items ; calculate the initial velocity (vi ) of a
Nerf Gun .This initial velocity is also called muzzle velocity. We will then fire it at given angles and compare range values.
It is also helpful to know that 3.05 ft €= 1m !
Purpose :To discover a practical way to measure the muzzle velocity of the Nerf gun, then use the Range equation to
verify this velocity
Materials to be used:
Stop Watch
Meter stick
Nerf Guns
Protractor
Step One
Devise a simple way to determine the initial velocity of the Nerf Gun in the x- dimension only. Describe the method here
and box in your calculated value (show work!). This will also serve as the muzzle velocity.
Step Two
Shoot the Nerf gun and angle of 30 , 45, 60 degrees from a horizontal reference (say, your shoulder ). Write down the
range achieved in meters. Use this range to calculate the initial velocity per launch. Show your work below.
30°
45°
60°
Analysis Questions
Question #1 Do a % of error for the original value you calculated (Step One) compared to each of the three trials (Step
P−A
Two). Recall that
and consider Step one your actual value.
A
€
x100 = %error
2
Question #2 Calculate the product Vi (Sin2θ) and record below for each trial
30°
45°
60°
2
Question #3 Use excel to plot a graph with range of the projectile on the x and Vi (Sin2θ) on the y. Be sure to calculate
the slope (y =…) Do not print this graph, briefly sketch it below using a ruler.
€
Vi^2[sin2theta] (m^2/s^2) Vi^2(sin2theta) vs Range Range(m) Question #4 What are the units for the slope of your graph ?
a) What physical constant does the slope of your graph represent!
Question #5 Give a brief summary of what you learned throughout this lab.