Force of Gravity Explained: a Practical Experiment

Introduction

Gravity is the force that attracts a body towards the center of the earth; a common example of gravity taking place is a falling object. When toast slides off a table, it is observed to land jelly side down frequently. As the toast is falling, it is accelerating, or undergoing a change in velocity, towards the ground; however, friction, the resistance that an object encounter when moving over another, must be accounted for because air resistance- the frictional force air exerts against a moving object- causes the object to slow down as it falls. The weight- a body's relative mass that gives rise to a downward force- of the jelly on the bread may be heavy enough to significantly alter the side it lands on when it falls because the weight of an object is know to affect the time it takes to fall due to the amount of air resistance applied to the object.

Objects with more mass fall with more gravitational force pulling on it while lighter objects are slowed down by air resistance more than heavier objects, thus heavier objects are expected to fall faster on earth. It is expected that a greater amount of jelly will cause the bread to land faster.

In this experiment, the observation was tested with the amount of jelly as the independent variable, while the dependant variable was whether or not the toast lands jelly side down. The control of the experiment was the bread that was marked one side with no jelly on it.

If there is more jelly on the bread, then it is more likely for the bread to land jelly side down.

Materials

• 4 pieces of bread
• 2 oz. jelly
• Triple beam balance
• Plastic knife
• Paper plate
• Paper for floor

Methods, Result, Discussion

The paper plate and the bread were weighed on the triple beam balance and recorded. Different amounts of jelly was spread on each slice of bread. Each slice of bread was weighed and recorded again with the jelly. Each slice of bread was pushed off the table to determine whether or not it landed on the jelly side for a total of three trials for each bread.

No correlation is shown between the mass of the jelly and the number of times the toast landed jelly side down. Out of all the trials, ten out of twelve times, the toast landed jelly side down. The only times the bread landed jelly or marked side up were the slice that contained no jelly and the slice with 16.5 grams of jelly.

The results show that the toast landed on the jelly side in almost all the trials. The only exceptions to the data may have resulted from the varying amounts of force that was applied too the toast as it was pushed off. Another explanation could have been the uneven spreading of the jelly on the bread, resulting in a possibility of the jelly coming off the bread as it fell.

In contrast to the rese arch conducted about gravity and free fall, heavier bread in this experience had no affect on the side of the bread it landed on. Although the bread with more jelly may have landed slightly faster, the height was not tall enough for the lighter bread to rotate 360 degrees before landing on the ground; therefore, the frequency of the toast landing jelly side down does no depend on the mass of the jelly.

Conclusion

According to the results of the lab, it is likely that the toast will almost always land jelly side down with no correlation to the mass of the jelly, thus disproving the hypothesis.