Answer Key • Lesson 3: Sink and Float - khmtb4.com

1 * answers and/or discussion are included in the Key Lesson 3: Sink and FloatStudent GuideSink and Float (SG pp. 538 541)Questions 1 201 2.* See Figure 2 in the Lesson for a sample In our sample data, paraffin has more massthan the rock. But paraffin floats in water andthe rock From the sample data table we can see thatclay sinks in water. In our sample data, woodhas less mass than clay and wood has more mass than clay and it alsofloats. Therefore, whether an object sinks orfloats does not depend only upon its *See Figure 2 in the Lesson for sample In our sample data, the piece of wood hasmore volume than the plastic or steel sphere,but wood From the data table we can see that claysinks in water.

2 In our sample data, the cork hasless volume than clay and cork floats. Paraffinhas more volume than clay and it also , whether an object sinks or floatsdoes not depend only upon its *See Figure 4 in the the mass of several objects. Record your results in the data table likethe one shown here on the Sink and Float Data Tablespage in the StudentActivity each object into a pan of water. Record in the table whether it sinks each of the objects that sink have more mass than the objects that Float ?If not, give an whether an object sinks or floats depend only upon its mass?

3 The volume of the same objects. Record your results in the table. each of the objects that sink larger in volume than the objects that Float ?If not, give an whether an object sinks or floats depend only upon its volume? gVVolumein ccSink or Float ?steel sphereplastic spherewaterSink and FloatRatioMVSG Grade 5 Unit 11 Lesson 3 Sink and Float538 Copyright Kendall Hunt Publishing CompanyStudent Guide- Page 538 Sink and FloatSG Grade 5 Unit 11 Lesson 3539 Copyright Kendall Hunt Publishing CompanyNow that you have collected and thought about your data, discuss againwhat properties of an object you think determine whether it will sink or or floating has something to do with both mass and volume.

4 If somethingis heavy for its size, it will sink. If it is light for its size, it will Float . We can measureheaviness by mass and size by volume. To help predict whether an object will sinkor Float , scientists compare an object s mass to its volume. To compare, they findthe ratio of the object s mass to its volume. This ratio is called For example, if a rock has a mass of M= 65 g and a volume of V= 23 cc, its density is Sinking and floating have something to do with density. We will explore this moreby finding the density of some objects and looking for patterns in the data tables like the ones below on the Sink and Float Data Tablespage in the Student Activity Book.

5 Write the density of each object as a ratioof its mass to Density as RatioFloats in WaterMV? g? ccObject Density as RatioSinks in WaterMV? g? ccMass Volume65 g 23 ccM VStudent Guide- Page 5391 TG Grade 5 Unit 11 Lesson 3 Answer KeyCopyright Kendall Hunt Publishing CompanyTG Grade 5 Unit 11 Lesson 3 Answer Key 2 Answer Key Lesson 3: Sink and Float9.* answers may vary. Possible patterns include:If the mass of an object is larger than itsvolume (in cubic centimeters) then the objectsinks in water; otherwise it floats. If the densityof an object (in grams) is greater than 11cgc , thenthe object sinks in water; otherwise it *Since the density of the object is 4300cgc ,which isless than 1 g/cc, the object will *We can t tell whether the object will sink orfloat.

6 We need to know its volume *The MV ratio of water is *The MV ratios of objects that sink aregreater than the MV ratio of water. The ratios of objects that sink are greater than *The MV ratios of objects that Float are less than the MV ratio of water. The ratios of objects that Float are less than *Neither; they both weight 1 * 1 pound of lead is more dense than 1pound of at your tables. What patterns do you see about objects that sink andthose that Float in water? Write your conclusions in object has a mass of 30 g and a volume of 40 cc. Will it sink or Float in water?

7 An object with a mass of 500 g sink or Float in water? do you notice about theM Vratio for water that is different than theM Vfor the other objects? do you notice about theM Vratios of the objects that sink in relation totheM Vratio of water? Is it less than 1 or greater than 1? do you notice about theM Vratios of the objects that Float in relation totheM Vof water? Is it less than 1 or greater than 1? is heavier, a pound of feathers or a pound of lead? is more dense, a pound of feathers or a pound of lead?SG Grade 5 Unit 11 Lesson 3 Sink and Float540 Copyright Kendall Hunt Publishing CompanyStudent Guide- Page 540* answers and/or discussion are included in the Kendall Hunt Publishing CompanyAnswer Key Lesson 3: Sink and Float3 TG Grade 5 Unit 11 Lesson 3 Answer KeyCopyright Kendall Hunt Publishing g ; g ; g will vary and show that the mass is greater than the volume.

8 M= ? > g; MV = ? > g will vary and show that the mass is less than the volume. M= ? < g; MV = ? < g volume was greater than the mass, so thecork > Since the steel sphere sinks, I chosea value for the mass of the sphere that wasgreater than its volume of * answers will vary. Students could makethe case that the ratios are equivalentbecause they are all close to one and thatthe straight best fit-line goes through thepoint (0,0). On the other hand, studentscould make the case that the ratios are notequivalent because they do not exactlyreduce to a common factor and are notequal to *The volume of the box is 10 cm 5 cm 10 cm 500 cc.

9 The totalmass of the boat (the mass of the empty boatand the mass of the load) cannot have morethan 500 g. If the ratio MV is greater than 1, theboat will sink. Thus, as long as the extra massis less than 350 g, the total mass will be lessthan 500 g and the boat will not 4050607080 Mass vs. Volume of WaterVVolume of Water (in cc)MMass (in gram)s (50, 49)s ( , 6)s (25, 25)s (35, )Sink and FloatSG Grade 5 Unit 11 Lesson 3541 Copyright Kendall Hunt Publishing Company Check-In: Questions 16 forgot to write down all the information on his Sink and Float and complete his data table for did you decide if the item in Question 16B was going to sink or Float ?

10 Did you choose the mass for Question 16D? and Jackie measured the volume and mass for different amounts ofwater and found the following ratios: 50 g/49 cc, 35 cc, 25 g/25 cc, 6 a graph for Mass vs. Volume of Water using the ratios and draw abest-fit line through (0, 0). Title your graph and label the the ratios equivalent? Write two reasons that support your Answer . boat in the shape of a boxis shown mass of the empty boatis 150 g. How much extramass can the boat holdbefore it sinks? Show and Float : JeromeSink orFloat?VVolume in ccObjectMMass in gsteel sphere(1 inch diameter)plastic cc10 cm10 cm5 cmStudent Guide- Page 541* answers and/or discussion are included in the Grade 5 Unit 11 Lesson 3 Answer Key 4 Answer Key Lesson 3: Sink and FloatCopyright Kendall Hunt Publishing CompanyHomework (SG p.)