Mass, Density, Volume, & Weight

Mass – What is it?

• Mass is the amount of matter an object contains.

• Matter is anything that has mass & takes up space

• Mass is ALWAYS constant• It doesn’t change depending on where

it is & it IS NOT dependent on gravity. • Measured by using a balance

comparing a known amount of matter to an unknown amount of matter

Weight – What is it?

• Weight is the measure of the force of gravity acting on an object

• Weight changes with location– For example, my dog, Asa weighs 13.4

lbs (6kg) on Earth. If he were sent into space, he would weigh NOTHING!

• His weight would change on different planets

• Different planets have different gravity fields

Weight – What is it?

• Measure of force of gravity acting on an object• Changes with location • Weight of an object changes if the gravity

acting on that object changes• Weight = mass x gravity• Measured with a scale– Measuring the pull of gravity

What is volume?

• Volume is the measure of the amount of space that a solid, liquid, or gas occupies

• There are several common units of measure for volume:– mL (liquids)– Cm3

How is volume measured?

• Direct measurement of liquid (units = mL)

• Displacement of liquid by a solid (units mL changed to Cm3 )

• L x W x H of a cube or rectangular solid (units are Cm3 )

What is density?

• Density is the amount of something in a particular area or space– The amount of “stuff” in a space

Calculating Density

• We can calculate density by using the formula: Density=mass/volume

• D= m/v

• (I) heart density!

Questions??

• Complete worksheets for class work/homework

• Ask questions if you need help!!