50 likes | 230 Views
Density. By: Megan Passmore. Sinker or Floater?. Floaters If an object has a lower density than the substance it’s placed in the object will float because it is too light to be pulled down through the dense substance.
E N D
Density By: Megan Passmore
Sinker or Floater? Floaters • If an object has a lower density than the substance it’s placed in the object will float because it is too light to be pulled down through the dense substance. • Ex. If Styrofoam is placed in water the Styrofoam will float because Styrofoam has a density of 0.15kg/L and water has a higher density of 1kg/L. Sinkers • If an object has a higher density than the substance it’s placed in the object will sink because it is being pulled down by gravity through the thin substance. • Ex. If aluminum is placed in water the aluminum will sink because aluminum has a density of 2.7kg/L and water has a low density of 1kg/L.
Calculating Density REMEMBER: The displacement method is very important and helping when attempting to calculate the volume of an irregular solid. To do this, fill a graduated cylinder with water, measure the current volume, place the irregular shape, and measure the new volume. Subtract the new volume by the previous volume to find the water displaced. The difference is the volume of the shape. REMEMBER: To calculate the density use the equation M/V=D, or mass divided by volume equals density. To find the mass of a substance, use a scale or balance. To find the volume of a substance, use a graduated cylinder or mathematical equation. Divide the two numbers to find the density of the object.
TRY IT! BEFORE: If a wooden block weighs 2kg and it’s volume is 5L, you’re going to divide the mass (2kg) by the volume (5L.) 2kg/5L=0.40kg/L. AFTER:
What is it? If someone hands you an unknown substance and says its something like diamond, how do you know if it really is? You have to observe the characteristics. You should know how they react to different substances and whether or not they float or sink in water. An example of this can be demonstrated through the Phet simulation. When you’re given a mystery substance, you can test whether it floats or sinks in water. Next, you can calculate the density by finding the mass and volume. Using the chart, you can determine the substances true identity.