Lesson 1: Length

T. Trimpe 2008 http://sciencespot.net/

English vs. Metric Units

Left Image: http://webapps.lsa.umich.edu/physics/demolab/controls/imagedemosm.aspx?picid=1167

Right Image: http://share.lancealan.com/N800%20ruler.jpg

Which is longer?

A. 1 mile or 1 kilometer

B. 1 yard or 1 meter

C. 1 inch or 1 centimeter

1.6 kilometers

1 mi= 1.6 km

1 mile

1 yard = 0.9444 meters

1 yd = 0.9444 m

1 inch = 2.54 centimeters

1 in = 2.54 cm

Metric Units

The basic unit of length in the metric system in the meter and is represented by a

lowercase m.

Standard: The distance traveled by light in absolute vacuum in 1⁄299,792,458 of

a second.

Metric Units

1 Kilometer (km) = 1000 meters (m)

1 km = 1000 m

1 Meter = 100 Centimeters (cm) 1m = 100cm

1 Meter = 1000 Millimeters (mm) 1m = 1000 m

Which is larger?

A. 1 meter or 105 centimeters

B. 4 kilometers or 4400 meters

C. 12 centimeters or 102 millimeters

D. 1200 millimeters or 1 meter

Click the image to

watch a short video

about the meter.

Measuring Length

Ruler: http://www.k12math.com/math-concepts/measurement/ruler-cm.jpg

How many millimeters are in 1 centimeter?

What is the length of the line in centimeters? _______cm

What is the length of the line in millimeters? _______mm

What is the length of the line to the nearest centimeter? ________cm

HINT: Round to the nearest centimeter – no decimals.

1 cm (centimeter) = 10 millimeters (mm)

1cm = 10 mm

1 decimeter (dm) = 10 centimeters (cm)1 dm = 10 cm

L. LaRosa http://www.middleschoolscience.com for T. Trimpe 2008 http://sciencespot.net/

Find the length (antennae to feet) of the following insects to

the nearest whole or half cm:

Find the length (antennae to feet) of the following insects to

the nearest whole or half cm:

L. LaRosa http://www.middleschoolscience.com for T. Trimpe 2008 http://sciencespot.net/

Find the lengths of the following pink lines to

the nearest mm:

Find the lengths of the following pink lines to

the nearest mm:

L. LaRosa http://www.middleschoolscience.com for T. Trimpe 2008 http://sciencespot.net/

Complete the following conversions:

3 cm = _____ mm

15 cm = ____ mm

49 cm = ____ mm

103 cm = ____ mm

5 mm = _____ cm

19 mm = ____ cm

74 mm = ____ cm

158 mm = ____ cm

Complete the following conversions:

3 cm = _____ mm

15 cm = ____ mm

49 cm = ____ mm

103 cm = ____ mm

5 mm = _____ cm

19 mm = ____ cm

74 mm = ____ cm

158 mm = ____ cm

Complete the following conversions:

3 cm = 30 mm

15 cm = 150 mm

49 cm = 490 mm

103 cm = 1,030mm

5 mm = 0.5 cm

19 mm = 1.9 cm

74 mm = 7.4 cm

158 mm = 15.8 cm

X 10 ÷ 10

L. LaRosa http://www.middleschoolscience.com for T. Trimpe 2008 http://sciencespot.net/

Find the lengths of the following pencils in cm & mm:

_____ cm _____ mm

_____ cm _____ mm

_____ cm _____ mm

_____ cm _____ mm

Images from http://www.bgfl.org/bgfl/custom/resources_ftp/client_ftp/ks2/maths/measures/index.htm

Find the lengths of the following pencils in cm & mm:

12.5 cm 125 mm

4 cm 40 mm

10 cm 100 mm

14.5 cm 145 mm

Images from http://www.bgfl.org/bgfl/custom/resources_ftp/client_ftp/ks2/maths/measures/index.htm

L. LaRosa http://www.middleschoolscience.com for T. Trimpe 2008 http://sciencespot.net/

Complete the following conversions

for centimeters and meters:

1,955 cm = ___ m

178 cm = ____ m

2,299 cm = ___ m

42 cm = ____ m

1. 8 m = ____ cm

0.56 m = ____ cm

2.3 m = ____ cm

0.02 m = ____ cm

Complete the following conversions

for centimeters and meters:

1,955 cm = ___ m

178 cm = ____ m

2,299 cm = ___ m

42 cm = ____ m

1. 8 m = ____ cm

0.56 m = ____ cm

2.3 m = ____ cm

0.02 m = ____ cm

Complete the following conversions

for centimeters and meters:

1,955 cm = 19.55 m

178 cm = 1.78 m

2,299 cm = 22.99m

42 cm = 0.42 m

1. 8 m = 180 cm

0.56 m = 56 cm

2.3 m = 230 cm

0.02 m = 2 cm

÷ 100 x 100