# AP Physics 2: 2.2 Object Interaction and Forces

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AP Physics 2: 2.2 Object Interaction and Forces. If the distance between the ball and the point charges is doubled, what is the new electric force exerted on the ball?

AP Physics 2 | Object Interaction and Forces |

Language | English Language |

Science Practice 1 | Using representations and models |

### Transcript

Well this column fries over there all right A small

electrically receptive ball is placed on the ground One point

charged with charge q Liza distance x north of the

ball while a second point charged with charge q lies

an equal distance x west of it If the distance

between the point charges and bolus doubled what's the new

electric force exerted on the ball All right assume that

the original electric force on the ball is well we

call it tea All right And here the essential And

they're so some version of pete a long long time

ago in a galaxy Well actually in our galaxy And

it wasn't that long ago actually let's Just start over

back in seventeen eighty five charles augustin to comb discovered

a law of physics which now bears his name And

no it's not charlie's law It's cooling is lost and

it states that electric force exerted at a point between

two point charges equals ghoulam's constant times the product of

the charges divided by the square of the distance between

the charges That's the equation right there Okay And because

of that last part we know that we have an

inverse square relationship at work We've seen this with radiation

from a point source Remember that if not it's Okay

we can't remember what we had for lunch All right

wait Even have lunch yet we're going to go You

can just be on safe sex Inverse square relationships mean

that numbers start getting really small quickly If the distance

triples the forces reduced to one night And if the

distance doubles well the force exerted is one quarter is

strong No the correct answer here is just a this

question involves two point sources but on the test there

might be questions with more sources So remember that charge

sources effect each other as well as non charge objects

like the ball Obviously the math gets a little more

complicated as we had sources but we're smart enough to

handle it Unfortunately we're not smart enough to wait for

the french fries school Before we stuff them in our 00:02:10.953 --> [endTime] mouth Ouch