Bridge Bolster Lab Report

Introduction

The intent of this experiment is to practice the scientific method, by constructing a bridge to bolster as many pennies as possible before it sags 1 1/8”, touching the desk. I hope to get a better perception of the scientific method by doing an experiment. I also hope to gain knowledge about the way bridges are structured to hold more weight. Based on my research, I know that the thicker the bridge is, the more weight it will bolster. Knowing this I formed a hypothesis. My hypothesis is the more index cards that the bridge is made out of, the greater amount of pennies it will bolster.

Methods

Materials: • 6 pink erasers

• 3 index cards

• 50 pennies

• Double sided tape

First make 2 balanced bridge supports out of 3 erasers each.

Secondly put an index card

Results

Data Table:

Number of index cards Number of pennies held Average Times 1 2 3

1 15 16 16 15 2/3

2 27 28 29 28

3 43 43 39 41 2/3

Observations:

Quantitative Qualitative

There were 2 bridge supports made out of 3 erasers each The erasers were rhombic prisms

The bridge supports were 3 1/8” apart The erasers were pink

The bridge supports were 1 1/8” high The bridge supports were balanced

The index cards were 3” by 5” The erasers were used

There were 3 bridges The bridges were index cards

The first bridge was 1 index card The second and third bridges had the index cards taped together

The second bridge was 2 index cards I put the pennies on the bridge in the same pattern

The third bridge was 3 index cards

The second bridge held about 12 more pennies than the first bridge

The third bridge held about 14 more pennies than the second bridge

When I added 1 more index card, it held on average, 13 more pennies