When an unbalanced force (net force) is applied to an object, the motion of that object will be changed. The change depends upon the size of the net force as well as the size of the object, size measured by its mass.

Newton's 2nd Law of Motion gives a relationship between the three variables, and you will work with them as you attempt to solve a specific problem in *dynamics*, the study of which motions come from which kinds of forces. In addition to answering a
specific problem, you will develop an experimental understanding of Newton's 2nd Law through your laboratory work.

**Purpose**

- Develop a understanding of how varying the net force on an object affects the acceleration
- Develop a understanding of how varying the mass of an object affects the acceleration
- Solve a specific problem involving a force applied to an object

**Procedure
**

1. Vary the amount of net force acting on the system, each time measuring the acceleration. Maintain the mass of the system constant as you complete this step. Use at least 5 different force combinations.

2. Vary the mass of the system, each time measuring the acceleration. Maintain the net force at a constant value as you complete this step. Use at least 5 different mass combinations.

3. Solve the specific problem stated for your particular piece of apparatus and experimental procedure.

**Analysis**

1. Construct a graph of acceleration versus force for step (1). Determine the mathematical equation and state the general relationship indicated by your graph.

2. Construct a graph of acceleration versus mass for step (2). Determine the mathematical equation and state the general relationship indicated by your graph.

3. Carry out the calculations necessary in order to solve your specific problem.

**Report
**

Prepare a formal written report, word processed, which contains the following sections:

Procedure

Data Tables

Graphs & Calculations

Discussion

In your Discusson, answer the points raised in the Purpose. Cite specific evidence from your experimentation to support your conclusions. Compare your results with the standard equation found in your textbook.

Use 3rd person impersonal voice as much as possible. One report per lab group.

Specific Problem
| Equipment | Setup | |

A | Make necessary adjustments in the mass of the cart and the hanging mass in order to achieve a linear acceleration of 2.40 m/s/s. Show your calculations and a data run. | Smart Pulley
Apple IIe Masses Laboratory Cart | |

B | Make necessary adjustments in the mass of the cart and the hanging mass in order to achieve a linear acceleration of 1.65 m/s/s. Show your calculations and a data run. | ULI
Motion Sensor Pulley Masses Laboratory Cart | |

C | Make necessary adjustments in the mass of the cart and the hanging mass in order to achieve a linear acceleration of 1.40 m/s/s up the slope. Show your calculations and a data run. | ULI
Motion Sensor Pulley 1.2 m Track Masses Laboratory Cart | |

D | Make necessary adjustments in the mass of the cart and the hanging mass in order to achieve a linear acceleration of 2.00 m/s/s down the slope. Show your calculations and a data run. | CBL
Motion Sensor Pulley 1.2 m Track Masses Laboratory Cart | |

E | Make necessary adjustments in the mass of the cart and the angle of the inclined plane in order to achieve a linear acceleration of 1.80 m/s/s. Show your calculations and a data run. | CBL
Motion Sensor Plane Masses Laboratory Cart | |

F | Make necessary adjustments in the mass of the cart and the angle of the inclined plane in order to achieve a linear acceleration of -1.20 m/s/s. Show your calculations and a data run. | Science Workshop
Motion Sensor Plane Masses Laboratory Cart | |

G | Examine the acceleration vs the angle of the fan. Determine the angle needed in order to achieve a linear acceleration of 0.150 m/s/s. Show your calculations and a data run. | CBL
Motion Sensor Fan Cart Masses | |

H | Make necessary adjustments in the two masses in order to achieve a linear acceleration of 2.50 m/s/s. Show your calculations and a data run. | Smart Pulley
Apple IIe Masses Ring Stand | |

I | Make necessary adjustments in the two masses in order to achieve a final velocity of 2.50 m/s after falling a distance that you provide. Show your calculations and a data run. | Smart Pulley
ULI Masses Ring Stand | |

J | Make necessary adjustments in the two masses in order to cover a total distance of 0.85 meters in a time of 0.90 sec. Show your calculations and a data run. | CBL
Motion Sensor Pulley Masses Ring Stand |

Submitted by Clarence Bakken. Posted 10/13/96