PASCO ME-6825A MINI LAUNCHER - Manual (Page 37)

012-05479B Mini Launcher
35
®
Experiment 10 (Demo): Shooting Through Hoops
EQUIPMENT NEEDED
– Mini Launcher and steel ball – (5) Ring clamps on stands
– (2) Photogates – Photogate Bracket
– Meter stick – (2) Meter stick
– (optional) Computer with Timing software
Purpose
The purpose of this demonstration is to show that the path of a ball launched horizontally from a table is
parabolic.
Theory
The range is the horizontal distance, x, between the muzzle of the Launcher and the place where the ball
hits, given by
where v
0
is the initial speed of the ball as it leaves the muzzle and t is the time of flight.
The vertical position, y, of the ball at time t is given by
where y
0
is the initial height of the ball and g is the acceleration due to gravity.
Setup
➀
Before the demonstration begins, find the initial velocity for the range setting to be used. Attach the
photogates and use a computer to find the initial velocity or shoot the ball horizontally and measure x
and y to find the initial velocity. See experiments 1 and 2.
➁
To prepare the demonstration, clamp the Mini Launcher to the table with the Launcher aimed away from
the table so the ball will land on the floor.
➂
Adjust the angle of the Launcher to zero degrees so it will shoot horizontally.
Procedure
➀
In front of the class, measure the initial height of the ball at muzzle level.
➁
Calculate the horizontal and vertical positions of the ball each 1/10 second until it hits the floor.
0.1
0.2
0.3
0.4
0.5
t (sec) x = v
0
t (cm) y = y
0
- ( 1 /
2
)gt
2
(cm)
x = v
0
t
y = y
0
-
1
2gt
2