EXP #3 PHYSICAL SCIENCE LABORATORY REPORT 1

Abstract

The goal of this lab is to determine an appropriate method of describing motion. This chosen

method, velocity, allows the observer to make statements and conclusions regarding different

aspects of an object’s motion. Utilizing a Hot-Wheels car, the observer will measure the velocity

of the car, as it moves along the track, using four different methods: 1. Measuring average

velocity with eye-hand coordination, 2. Measuring average velocity using two photogates, 3.

Measuring instantaneous velocities at two locations and then averaging the two values, 4.

Measuring instantaneous velocity at a single location. The experimental data indicates that the

average velocity of the car is 188.68±0.4 cm/sec and the instantaneous velocities are

169.333±1.25 cm/sec, 197.44±3.333 cm/sec, and 183.39±2.29 cm/sec respectively. A larger

collection of multiple data suggests that the average velocity of the car is 201.814±0.7958 cm/sec

and the instantaneous velocities are 185.6572±3.4218 cm/sec, 215.728±4.6666 cm/sec, and

207.228±3.548 cm/sec respectively. Overall, all results assist the observer in developing a more

concrete understanding of velocity, both average and instantaneous.

Introduction

This lab allows the observer to describe an object’s motion by calculating average and

instantaneous velocity. Average velocity, or Vaverage, is calculated by finding the average time the

car takes to travel a distance, d, from B to C. The formula Vaverage ± ΔV =

is used to find the

average velocity, where d is 100±0.01 cm and t is the average time calculated from three trials.

The uncertainty, ± ΔV, is calculated by calculating the largest difference between the computed

average time t and any one of the trial values. The instantaneous velocities are calculated in a

similar way, but utilize either LB, length of the flag-width, or LC, length of the car, respectively.

EXP #3 PHYSICAL SCIENCE LABORATORY REPORT 2

The two formulas are Vat c ± ΔVC =

and Vat B ± ΔVB =

. This lab allows the observer to both

visualize and calculate velocity and therefore develop a complete understanding of the concept.

Conclusion

The results from this lab assert that velocity is distance over time, and that there is a difference

between average velocity and instantaneous velocity. Average velocity represents the change in

location over the time required to make that change. Instantaneous velocity represents the

velocity at both a specific time and location. It is important to note that although both values can

work independently, an examination and consideration of values allows for a more complete and

thorough understanding of a given object’s motion. The average velocity gives and overview of

the general motion of the object and instantaneous velocity provides the observer a closer in-

depth view of a single moment during the motion of the object.