Do Now• On a new, never before used piece of LOOSE

LEAF (you can use scrap paper OR a piece of loose leaf ripped in half feel free to share!): – Create 5 metric conversion problems.

Examples:

• 10 cm = ______mm OR• Which is greater: 120 cm or 102 mm

• Do not use exact problems from yesterday! • Also, do not answer/ complete the

problems yet…

Or…. Use Conversion Factors

1030 cm = ______ m?

1030 cm = __1_m 1 100 cm

1030 m100

10.30 m

Unit Conversion

Lesson 2: Mass

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

English vs. Metric Units

Which is larger? (*On Earth, at Sea Level*)

1. 1 Pound or 100 Grams

2. 1 Kilogram or 1 Pound

3. 1 Ounce or 1000 Milligrams

1 pound = 453.6 grams

1 kilogram = 2.2pounds

1 ounce of gold = 28,349.5 milligrams

Metric UnitsMass refers to the amount of matter in an object.

The base unit of mass in the metric system in the kilogram and is represented by kg.

Standard: 1 kilogram is equal to the mass of the International Prototype Kilogram (IPK), a platinum-iridium cylinder kept by the BIPM at Sèvres, France.

Metric Units

1 Kilogram (kg) = 1000 Grams (g)

1 Gram (g) = 1000 Milligrams (mg)

Which is larger?

A. 1 kilogram or 1500 grams

B. 1200 milligrams or 1 gram

C. 12 milligrams or 12 kilograms

D. 4 kilograms or 4500 grams

Kilogram Prototype

Kilogram Prototype Image - http://en.wikipedia.org/wiki/Kilogram

Measuring Mass

Top Image: http://www.southwestscales.com/Ohaus_Triple_Beam_750-SO.jpgBottom Image: http://www.regentsprep.org/Regents/biology/units/laboratory/graphics/triplebeambalance.jpg

We will be using triple-beam balances to find the mass of various objects.

The objects are placed on the scale and then you move the weights on the beams until you get the lines on the right-side of the scale to match up.

Once you have balanced the scale, you add up the amounts on each beam to find the total mass.

What would be the mass of the object measured in the picture?

_______ + ______ + _______ = ___________ g

Measuring Mass – Triple-Beam Balance

1st – Place the item(s) on the scale.

2nd – Slide the large weight to the right until the arm drops below the line. Move the rider back one groove. Make sure it “locks” into place.

3rd – Repeat this process with the top weight. When the arm moves below the line, back it up one groove.

4th – Slide the small weight on the front beam until the lines match up.

5th – Add the amounts on each beam to find the total mass to the nearest tenth of a gram.

**YES, BUT…How would you mass, for example, a handful of marbles, on the triple beam balance?**

PRACTICE PROBLEMS!

105 g = ______________________ mg

27 kg = ______________________ mg

1.9 g = _____________________mg

6.3 kg = ______________________ dg

4.7 mg = __________________kg Circle the BEST metric unit for each:

(1)Your mass: mg g kg

(2) Amount of spices in a batch of cookies: mg g kg

(3) Mass of 10 pennies: mg g kg

Last Night’s HW Answers:Last Night’s HW Answers:1.Check your work2.Make corrections – you may work with people around you3.Have a question? Ask a peer or ask a teacher4.Didn’t do HW? Remember, quizzes are open note – you will want to write down these questions and answers so you have complete notes. Take a new copy of the HW if you lost yours, or download from my website.

Last Night’s HW Answers:Last Night’s HW Answers:1)2.5 km OR 2.500 km2)4.8 m OR 4.80 m3)0.0075 L OR .0075 L4)65,000 mg5)5,600 g6)0.5 m OR 0.50 m7)63 mm8)0.8257 cm OR .8257 cm9)560 cm10)0.12 g OR 0.120 g OR .12g OR .120 g

Make corrections; ask for help if needed.

IMPORTANT: CHECK TO MAKE SURE ALL MATERIALS ARE PRESENT BEFORE YOU BEGIN.Have your materials manager sign the sheet at teacher’s desk.

Materials That Should Be at Your Table:•Are listed in your supply bin, located at each lab bench.•Please verify that ALL MATERIALS are present and sign off at my desk. •If any materials are broken, damaged, and/or missing, please notify the teacher IMMEDIATELY so that the prior lab group can be addressed.