Introduction to Physical Science Mass and Weight Lesson 1

What is Physical Science Do Now Journal Entry: In your own words, define physical science. Definition: sciences concerned with inanimate natural objects including physics, chemistry, astronomy, and related objects Physical Science Matter Energy Chemistry Physics Basic Chemistry Sub-atomic particles Chemical reactions Explain why objects move the way they do

Matter What exactly is matter? Anything that takes up space and has mass Mass: amount of matter an object is made out of

Matter Journal Entry: Is air matter? YES! Air is Matter You can fill an empty balloon with air and it occupies the space Filling up a bike tire Pressure = m/v  air must have a mass if it exerts pressure Matter in air is what supports the weight of a plane or the weight of clouds Average cloud weighs one million pounds

From Matter to Mass How is Mass related to Matter? The mass of an object is a measure of the object’s inertial properties  the amount of matter it contains The basic unit of mass is kg Smaller items will be measured in g Mass = Volume x Density M (kg/g)=V (Solids cm^3/Liquors L )x D (kg/cm^3) Mass=Force/Acceleration M(kg/g)=F(N)/a (m/s^2) How do we measure Mass? Triple beam or electronic balance There are different ways to calculate mass

Mass vs Weight What’s the difference between mass and weight? The mass of an object is the amount of matter that the object contains Weight is the amount of gravitational force that is applied to an object Think about traveling to the moon…Would you weight the same amount? CLASS ACTIVITY Calculate weights on different planets

Calculating Weight on the Moon 9.8 N/kg 1.6 N/kg 3.7 N/kg 25 N/kg Things you need to know Weight (N) = Mass (kg) x Acceleration of gravity (N/kg) W=MxA

Calculating Weight on the moon Bruce weighs 185 lbs on Earth how much will he weigh on the moon? Convert weight into the same unit (lbs  kg) Weight and Mass have the same NUMERICAL value on Earth BUT are measured in different units, therefore they are not the same. The Acceleration of gravity (9.8 N) equals 1 kg. Calculate weight (N) value on Earth by pulling in numbers into the equation Calculate weight (N) value on the moon by pulling in equation Divide the weight (N) on the moon/planet by Earth Earth W = MxA W=84 kg x 9.8 N/kg 823.2 N Moon W=MxA W = 84 x1.6 N/kg 134.4N 134.4/823.2=0.16 You weigh 1/6 of your weight on the moon.

Class Activity Calculate the weight on Mars Calculate the weight on Jupiter Sam weighs 100 lbs on Earth. How much will they weigh on Mars? An African forest elephant weighs 6,000 lbs how much does it weigh on Mars? A German Shephard weighs 70lbs. How much does it weigh on Mars? What is the % of weight from Mars to Earth? My cat weighs 14 lbs on Earth. How much will he weigh on Jupiter? Alex weighs 30 kg. What is their weight on Jupiter? New York rat weight 2 kg. What is it’s weight on Jupiter What is the % of weight from Jupiter to Earth? 45 kg x 9.8 N/kg = 441 N 6.36 x 9.8 = 62.36 45 kg x 3.7 N/kg = 166.5 N 6.36 x 25 = 159 166.5/441 = .38 159/62.36 = 2.55 2727.27 x 9.8 = 26727.27 N 30x9.8=294 2727.27 x 3.7 = 10090.90 N 30x35=750 10090.90/26727.27 = .38 750/294 =2.55 31.89x9.8=312.52 2x9.8 =19.6 31.89x3.7=117.99 2x25=50 117.99/312.52=.38 50/19.6 = 2.55 W (N) = M(kg) x A (N/kg) kg = lbs/2.2

Converting Weight from N to lbs Weight = Mass x Surface Gravity So, if you know your weight on Earth and the surface gravity on Earth, you can calculate your mass. You can then calculate your weight on any other planet by using the surface gravity of that planet in the same equation. Find the weight of the following on each planet Sam 100 lbs Elephant 6,000 lbs My cat 14 lbs NY Rat 4.4 lbs Surface gravity ratio’s compared to Earth Mercury  .38 Venus  .91 Earth  1.0 Mars  .38 Jupiter  2.34 Saturn  .93 Uranus  .92 Neptune  1.12

Mass and Weight Venn Diagram Definition Effect of Gravity How is it measured Units Weight Mass: amount of matter in an object No change in gravity Triple beam balance scale Kilograms Weight: amount of force (gravity) acting on an object Effect: More gravity more weight Spring scale Newtons Same: only related by the gravitational constant between them

Summary Mass=Volume x Density Mass=Force / Acceleration M=VxD Mass=Force / Acceleration M=F/A Triple Beam Balance Definitions: Mass Matter Weight

Homework In the back of your notebook/binder create a vocab section. Define: Matter, Mass, and Weight