Physical Science Practical Investigation

Grade 11 Physical Science Practical Investigation

Matthew Symes 2011/03/10

Aim:

To prove that differing masses, in an isolated system, fall at the same rates.

Hypothesis:

Objects of differing mass will have the same gravitational acceleration in an isolated system.

Method:

1. Record the masses of three objects of roughly the same shape, varying in mass, but not light enough for air resistance to affect the recordings. Eg. 0.15, 5 and 20 kg's

2. Drop objects from a constant height, high enough for time to be accurately recorded. Minimise external factors eg. Wind. Measure this height and record it.

3. Using an accurate stopwatch, record the amount of time it takes the objects to fall from point of release to when it comes in contact with the ground.

4. Write down the results.

5. Repeat steps 2-4 a further four times.

6. Record the results in a table.

7. Use an equation of motion to calculate the change in velocity and then the acceleration of the object, record these results in a new table.

8. Using the tables draw a graph comparing the acceleration of the objects.

Results:

Table recording the time taken for 3 objects of different masses to fall 3,6m

Mass of object (kg) Time taken (s)

Recording 1 Recording 2 Recording 3 Recording 4 Recording 5 Average

0.15 0.86 0.86 0.84 0.88 0.83 0.854

5 0.87 0.84 0.86 0.81 0.86 0.848

20 0.92 0.89 0.84 0.82 0.85 0.864

Table showing the Change in velocity and acceleration of different masses falling from a height of 3,6m

Mass (kg) Average time (s) Average change in velocity (ms-1) Average