HONORS PHYSICS
PROJECTILE MOTION
PHYSICS QUEST 2 ________________
PART I. The animation shows a comparison of a projectile thrown horizontally to an
object in free-fall.
1. In the absence of air resistance, why does the horizontal component of velocity for a
projectile remain constant, and why does only the vertical component change?
2. How does the downward component of the motion of a projectile compare to the
motion of free fall?
3. At the instant a ball is thrown horizontally over a level range, a ball held at the side of
the first is released and drops to the ground. If air resistance can be neglected, which
ball - the one thrown or the one dropped from rest - strikes the ground first?
PART II. Both simulations show a situation where a plane and a truck are moving at
constant speed. The plane drops a package from its luggage compartment and the
truck projects a ball upward.
4. Neglecting the effects of air resistance, explain why after being thrown, the package
remains directly below the plane and the ball remains directly above the truck.
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PART III. SIMULATIONS
We will use computer simulations to investigate the effect of initial velocity, launch angle
and air resistance on an object experiencing projectile motion.
VIRTUAL LAB 1
A) INITIAL VELOCITY
- Check the box titled "Show Trails".
- Set the angle to 45˚
- Set the Velocity to 10 m/s
- Click FIRE
- Complete the data on the table.
- Repeat the procedure for the different initial velocities.
Initial
Velocity
(m/s)
Range x
(m)
Maximum Height y
(m)
Final Velocity vf
(m/s)
10
20
30
40
50
Total
Time
(s)
1. Check the variable(s) that changed with the initial velocity:
_____Range
_____Maximum Height
_____Final Velocity
_____Time
2. Check the variable(s) that did not change with the initial velocity:
_____Range
_____Maximum Height
_____Final Velocity
_____Time
B. LAUNCH ANGLE
- Refresh the page
- Set the Velocity to 50 m/s
- Set the angle to 10˚
- Click FIRE
- Complete the data on the table.
- Repeat the procedure for the different launch angles.
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Launch
Angle
Range x
(m)
Maximum Height y
(m)
Final Velocity vf
(m/s)
Total Time
(s)
10˚
30˚
45˚
60˚
80˚
1. Which angle has the maximum range?
2. Which angle has the maximum height?
3. Write two pairs of launch angles that had the same range:
1. ___________ and ___________
2. ___________ and ___________
Add each pair of angles, what pattern do you observe for these angles?
4. A projectile is launched at an initial speed of 50 m/s with a horizontal angle of 76°.
Use the simulation to answer these questions:
a. What is its range?
b. Give another angle that will produce the same range: __________
Does the simulation verify your prediction?
c. What is the sum of the two angles that produce this range? _________
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VIRTUAL LAB II. HOLE-IN-ONE
1. Use the TRAILS and NO AIR options.
2. Set the Green on the Horizontal Distance and the Launch Angle and LAUNCH.
3. Try with different velocities until you hit HOLE-IN-ONE.
4. Record this Velocity.
5. Repeat steps 1-3 using the AIR option.
LAUNCH ANGLE: 30
Horizontal Distance
(m)
Velocity (m/s)
NO AIR
Velocity (m/s)
AIR
Velocity (m/s)
NO AIR
Velocity (m/s)
AIR
200
400
LAUNCH ANGLE: 45
Horizontal Distance
(m)
200
400
1. In the previous virtual lab you found that the maximum range was achieved by a
________ launch angle.
How does the range (horizontal distance) achieved compare when there is air
resistance?
2. How did you have to modify the velocities when air resistance was present?
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