**Problem:** What is the relationship between the distance an accelerating
object travels and the time it takes to travel that distance?

__NOTE: DO
NOT BEGIN YOUR EXPERIMENT UNTIL EACH PERSON IN YOUR GROUP HAS
READ THE BACKGROUND AND COMPLETED THE BACKGROUND QUESTIONS.__

**Background
and Inquiry: **Why will a penny dropped off the Empire State
Building become a deadly object? It is because objects in free-fall
accelerate. The further they drop the faster they travel. By the
time the penny reaches the ground it will be traveling faster
than a racing car. Galileo was the first scientist to prove that
all objects fall at the same acceleration. We will notice a difference
however if we drop a piece of paper. The paper has a different
acceleration because of air pressure and frictional forces.

It is difficult to study the motion of falling objects because they are moving too rapidly. Take each of the balls (handball and Ping-Pong ball). Drop them from a feet high. Can you observe any changes in velocity? Drop the balls from a height of only one foot. Drop the balls from different heights and observe and discuss with your group what you observe.

By using an inclined plane we may slow the movement of accelerating objects. Today you will study acceleration in an experiment by rolling a ball down an incline plane. Acceleration is defined as a change in velocity. Velocity is defined as a change in distance per unit of time. Acceleration occurs because a force is applied to an object. As long as the force is applied the object will accelerate. In the case of falling objects the force applied is gravity. As the ball begins to move under the force of gravity it will accelerate. The further the ball goes the faster it will travel.

**Background
Questions: **

1) What is
velocity?

2) What is acceleration? How is acceleration different from velocity?

3) What are some conditions that will change the acceleration
of the rolling objects?

4) If a rock and a feather are dropped on the moon why do they
fall at the same rate while on earth they do not?

5) Would friction or air pressure affect how fast a ball rolls
down a incline? Why?

**Hypothesis: **State your hypothesis. Justify your statement!

**Materials**:
Inclined plane, two meter sticks, ping pong ball, handball, golf
ball, 2 digital watch timer.

__Diagram: __Include a diagram in you lab report.

**Procedure:**

1) Copy Table I , Table II, Table III.

2) Set up the equipment as shown in in class.

3) Set the incline plane for 35 degrees. You will record the time
it takes the ball to roll down the incline every 20 cm. There
should already be 20 cm. marks on the incline.

4) Start with the ping pong ball. Let the ball start rolling from
0 cm. Start your timer.

5) When the ball reaches the 20 cm. stop your timer. Let the ball
roll off the incline.

6) Record your time in Table I (see results section). *Repeat
a second time. Then average the two times.*

7) Repeat the process and record the time it takes till the ball
reaches the 40 cm. mark, 60 cm. Mark etc....

8)Record your data in Table I.

9) Set the
incline for 40 degrees and complete Table II.

10) Repeat steps 5-9 using the handball instead of the ping pong
ball.

**TABLE I** --Incline set at 35 degrees -- ping pong ball

Distance (cm.) |
(Trial I) |
Time (Sec) Student II (Trial II) |
Avg. Time (T) |

20 | |||

40 | |||

60 | |||

80 | |||

100 | |||

120 | |||

140 | |||

160 | |||

180 |

**TABLE II **Incline set at 35 degrees -- Blue Handball

Distance (cm.) |
Time (Sec) Trial I |
Time (Sec) Trial II |
Avg. Time (T) |

20 | |||

40 | |||

60 | |||

80 | |||

100 | |||

120 | |||

140 | |||

160 | |||

180 |

**PART II:**

In this experiment
you will study the effect that changing the angle of the incline
will have on the force of a rolling golf ball. Remember that Newton's
Second Law of motion states that *F = ma (Force = mass x accleration). *Does this mean that if an object has a greater acceleration
it can apply a greater force?

1) For table III below you will change the angle of the incline.

2) Set the paper cup at the end of the incline so the golf ball will roll into the cup.

3) Roll the golf ball from the top of the incline and measure how far the cup travels. It does not matter what part of the cup you use for your measurements as long a you always use the same part in your calculation.

**TABLE III **--

Angle of Incline |
Dist. Cup Moves (Trial I) |
Dist. Cup Moves (Trial II) |
Average Distance |

5 degrees | |||

10 degrees | |||

15 | |||

20 | |||

25 | |||

30 | |||

35 | |||

40 | |||

45 |

**Graphing: **

1) Make plots for Table I and Table II on the same graph. Plot
time on the y-axis and distance on the x-axis.

2) Make a graph of Table ^{ III, plotting the angle of incline
on the x-axis and the distance the cup moves on the y-axis.}

**Discussion:**

1) What are
the independent and dependent variables for table I and II?

2)
What are the independent and dependent variables for table III?

3) What are some factors held constant in each experiment?

4) What type of relationship is observed for your graphs in table
I and table II, linear or non-linear? Why is this the case?

5) If all objects accelerate at the same rate explain your differences
between the handball and ping pong ball.

6) Why did increasing the angle of the incline in Table III cause
the cup to move further away?

7) What type of relationship is observed for table III. Why do
you think this is the case?

^{}

**Applications**:
Design an experiment to determine the rate of acceleration of
a falling object.

What is a mathematical relationship and WHAT ARE THE DIFFERENT TYPES OF MATHEMATICAL RELATIONSHIPS that apply to the laboratory exercises in the following activities.

**Lab 1:
The Spring Constant ** -- __Problem:__ What is the relationship between how much a spring stretches and the force pulling on the spring?

**Lab 2:
The Pendulum** -__-Problem:__ What is the relationship between the period of a pendulum and the length of the string of the pendulum?

**Lab 3: Mass, Volume and Density**-- __ Problem: __What is the relationship between the mass of a ball and its volume assuming a constant density?

**Lab 4: Light Intensity**--__ ____ Problem: __What is the relationship between the intensity of a beam of light and the distance from a light source?

**Lab 5: Acceleration--** __Problem: __What is a the relationship between how the distance travels and the time in travel for an accelerating object?

**Lab 6: Polarization **-- __Problem:__ What is the relationship between how much light passes through a Polaroid filter and the angle the filter is rotated?

**Lab 7: Ohms Law**-- __Problem:__ What is the relationship between current, voltage when there is a constant resistance in an electric circuit.

**Lab 8: Radioactive Decay-**- __Problem:__ What is the relationship between the decay of radioactive material and the time allowed for the decay?

**Lab 9: Water Pressure**--__ Problem:__ What is the relationship between water pressure and depth of water?

**Lab 10: Attractive and Repulsive Forces**-- __ Problem:__ What is the relationship between the distance between two magnets and the force between them?

**Lab 11: Damping Motion**-- __Problem:__ What is the relationship between the height a ball bounces and the number of times it has bounced?

**Lab 12: Buoyancy **- Problem: What is the relationship between the volume of a boat and the weight it can hold?