AP Physics 1: 1.4 Properties of Objects and Systems

AP Physics 1: 1.4 Properties of Objects and Systems. What is the difference between inertial and gravitational mass?

AP Physics 1Properties of Objects and Systems
LanguageEnglish Language
Science Practice 3Engaging in scientific questioning

Transcript

00:19

be the same thing right Well in order to prevent

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him from failing the next physics quiz how should you

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respond and hear the potential answers that All right we'll

00:34

get started Let's talk inertia way all know what gravity

00:38

is and no we're not talking about sandra bullock movie

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although it was pretty cool and it did bank has

00:42

reconsider our dream of being an astronaut You may have

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heard someone say a body at rest tends to stay

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at rest and a body in motion tends to stay

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in motion The person who first spoke these words was

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yes sir isaac newton yet the same old guy who

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took an apple to the head and figured out gravity

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and he didn't say it exactly like that because they

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spoken is funny way back then but that's the gist

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of newton's first law of motion what this means is

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that if you have a bowling ball sitting on a

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table that ball isn't going to just start moving on

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its own force needs to be applied to it to

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make it move and once it's moving force needs to

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be applied to make it stop moving or to make

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it change direction that force can be friction or something

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that can apply a direct force to stop the motion

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So if we know what inertia is We can understand

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inertial mass inertial mass is a measure of an object

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tendency to resist change is in motion the mohr inertial

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mass an object has the more it resists change like

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your aunt who still thinks it's nineteen eighty six now

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gravitational mass is calculated using an object gravitational weight but

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don't confuse mass and weight They're not the same thing

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mass doesn't change Sandra bullock has mass no matter where

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she is but wait requires gravity that's why sandra can

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be weightless in space she's not being pulled down by

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the earth's gravitational force or by george clooney to calculate

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an object gravitational mass We need to know the objects

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weight and the force of gravity So when we put

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all this knowledge together we see that the correct answer

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is option A inertia refers to an objects resistance to

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change while the gravitational mass is the mass calculated from

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an object gravitational weight option b is wrong because the

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values aren't different and objects inertial mass is the same

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as its gravitational mass differences just in how they're measured

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see gets it wrong because mass never refers to volumes

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plus uses the definition of inertial master To find gravitational

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and option d is wrong because the formula used to

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calculate the types of masses is the same So if

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inertial mass and gravitational masters equal to each other why

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do we need to know the diff Well it's Because

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they let us describe mass in different ways And that

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lets us think about mass in different ways Being able

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to think about things in different ways is always helpful

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in physics or well any other branch of science and

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know our inertial mass doesn't quadruple on those saturday mornings

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Just