phys (1 Viewer)

[marioyoshi]

can someone help bowlkho 2011 physics
why do all objects accerate at the same rate on the eraht's surface
multiple choice question 1

 

[marioyoshi]

bmup

 

[Suu]

I'm going to assume that you are talking about "erath", a town in Louisiana, US. https://en.wikipedia.org/wiki/Erath,_Louisiana


On a more serious note, what are the choices for the answer?
The question seems a little bit vague to be honest.

 

[EMKsquared]

The fact that all objects accelerate at the same rate can be mathematically shown in the formaula which equals the gravitational acceleeation that is caused by the planet(cant type it here). As seen from the formula the gravitational acceleration experienced is only dependent on the gravitational constant and the mass and radius of the planet, independent on the mass of any given object experiencing this acceleration. It could also be understood by the formula f=ma, and rearranged a=f/m. Although your original assumption would be a higher force equates in a higher acceleration is incorrect as a higher force is required to accelerate the higher mass object to the same acceleration, which on the Earths surface is 9.813....m/s/s, depending on where you are of course. Hope i explained that well , common misconception which always befuddles the majority of physics students

 

[marioyoshi]

the options were
a) gravitational force on each object is the same
b) gravitational force on each object is proportional to its mass
c) the acceleration is directly proportional to the gravitational force acting on each mass
d) the acceleration is directly proportional to the mass of the object

 

[marioyoshi]

thx, but the answer was b, "the gravitational force on each object is proportional to its mass". how does this then relate to the acceleration

 

[Suu]

Simple.
Force= mass x acceleration.
if acceleration is constant (it is not, but it should be assumed it is for this question), than the more mass an object has, the more gravitational force it has. (probably not the best wording, but meh.)

 

[JackPatel]

bad question

 

[billykon]

The correct answer is clearly B. If you rearrange the formula a=F/m, you'll see that a massive object even though it experiences a bigger force than a smaller object, F=m1M2/r^2, it also has a greater mass, as a result both objects will experience the same acceleration. So that means the bigger the force an object experiences the bigger its mass is, therefore proportional. Although I could see why someone would pick C as the correct answer.