Justin Geeslin

Eng Physics I - M 1:00

Experiment One - Measurements

 

 

 

 

 

 


  1. Introduction

This experiment involves obtaining important values by directly measuring and by indirectly deriving using given equations. The types of measuring tools in this experiment vary greatly. Also, one must be able to detect the precision of a measuring tool as well as calculate the amount of error present in a quantity.


  1. Procedure

The first measurement will pertain to a large object such as the lab table top. The length, width, and thickness of the lab table were obtained by measuring the table with a meter stick. Two measurements were taken on different parts of the table for redundancy. The average between the two measurements were taken and recorded. The volume of the top the lab table can then be calculated from an accurate measurement by multiplying the length by the width by the height. The volume will be recorded in m3 and in cm3.

The second measurement pertains to a very thin object. For this reason a meter stick is not an appropriate measuring tool. For precision on a very thin object it is good to use a vernier caliper. To measure the thickness of one sheet of paper, measure the thickness of twenty sheets and divide that value by 20. Measure the twenty sheets twice with both tools. Measure twice with the meter stick and twice the caliper. Record the data and derive the average. Once the data is recorded, check the accuracy of your measurements by directly measuring the thickness of the once sheet with a micrometer. Record the result.

Next, the measurements will allow for the computation of an objects density. With four different objects, the mass will be computed by weighing the objects on a lab balance. The volume of the object will be computed according the table below. One can find the Experiment Density by dividing mass by volume (M/V). The accepted density is given. The irregular object is a special case. There is no proprietary formula for computing the volume therefore; the volume must be measuring by submerging the object in water and measuring the displacement. The mass of the irregular object is given. It is usually written on the side of the object.

The following measurements will attempt at the determination of π. The value of π is determined dividing the circumference by the diameter. The vernier caliper is used to measure the diameter of the three cylindrical objects. Next, the circumference must be found. This value is found by using a piece of string to wrap around the cylindrical object and then, measure the length of the piece of sting required to encircle the object.

  1. Observations

Measurement

Length (m)

Width (m)

Thickness (m)

1

1.51 m

1.08 m

.045 m

2

1.49 m

1.055 m

.04 m

Avg.

1.5 m

1.068 m

.0425 m


Volume (m3) : 0.068 - Volume (cm3) : 6.8


Measurement

Thickness : Ruler

Thickness : Vernier

1

.2 cm

.15 cm

2

.3 cm

.18 cm

Avg.

.25 cm

.165 cm

Thickness of single page using ruler : 0.01 cm

Thickness of single page using vernier : 0.1 mn – Precision of Vernier : 0.01

Thickness of single page micrometer : 0.8 m – Precision of micrometer : 0.01 nm


Measurement

Solid Cylinder

Hollow Cylinder

Block

Sphere

Diam.

Height

Dout

Dinner

Height

Depth

Length

Width

Height

Diam.

1

1.6

2.4

1.95

.95

6.2

4.83

4.85

2.6

1.3

1.9

2

1.55

2.4

1.93

.93

6.2

4.8

4.85

2.53

1.3

1.9

Avg.

1.575

2.4

1.94

.94

6.2

4.82

4.85

2.565

1.3

1.9


Volume of Solid Cylinder : πr2h - Volume of Sphere : (4/3)πr3

Volume of Hollow Cylinder : External Volume – Internal Volume

Volume of Rectangle : Length x Width x Height


Object

Mass

Volume

Experimental Density

Accepted Density

Solid Cylinder

12.2g

4.825 cm3

2.528 g/cm3

2.7 g/cm3

Hollow Cylinder

38.5g

14 cm3

2.75 g/cm3

2.7 g/cm3

Block

42.4g

15.95 cm3

2.66 g/cm3

2.7 g/cm3

Sphere

28.8g

3.591 cm3

8.020 g/cm3

8 g/cm3

Irregular

50g

7 mL

7.143 g/cm3

7.86 g/cm3


Measurement

Diameter

Circumference

π

1

1.9

5.97

3.14

2

1.9

4.71

3.14

3

1.9

5.15

3.14


Questions

  1. According to our calculations, the micrometer proved to be much more accurate because the device has a higher precision for small objects.

  2. Because of the values of our experimental density we can detect the material of each object. The solid cylinder, hollow cylinder, and the block all had similar densities. For that reason we can predict that all three are the same material and that material is aluminum. The sphere, however, returned a much greater density. The sphere, in this case, consists of steel.

  3. The experimental value derived by dividing the circumference by the diameter came surprisingly close the accepted value. The exact experimental value was 3.14210 as compared the accepted 3.14159.