Sample Report On Experiment __: Instantaneous Velocity In One Dimension

Purpose

The purpose of this laboratory experiment is to measure the instantaneous velocity of an object moving along a straight line.
Theory
Instantaneous velocity is not the same as average velocity. Average velocity is a measure of the distance traveled by an object in an interval of time, Δx/Δt. However, a moving object often changes its speed during its motion. Instantaneous velocity is the rate of change of velocity in an instant, Δx/Δt with lim Δt →0 s.

Apparatus and Procedure

In this lab, we measure the instantaneous rate of change of motion of an object along a straight line. A toy car is placed on a metal track that is 180 cm in length and given a push. Using a meter stick and calipers, we marked 9 separate distance intervals along the track. As the car moved along the track, a computer program was used to measure the time it took for the car to pass through each interval.

Results

Figure 1: Δx (the distance interval), Δt (measured time interval), and σΔt (standard deviation of the time interval) for 9 intervals along the track.
Figure 2: The standard deviation in velocity at each position along the track.
Figure 3: The average velocity of the car at each position along the track.
Figure 4: Average Velocity vs. Distance. The y-axis represents average velocity in m/s, the x-axis represents the distance in m along the track.
The instantaneous velocity of the object is the rate of change, or slope, of the line in the figure above.