Question

Choose the answer that shows the proper --definition of acceleration.
-- How far an object travels in a given time interval, including direction.
-- How far an object travels in a given time interval, regardless of direction.
-- How much the velocity of an object changes in a given time interval and what direction it is in.
-- The change in position of the object with respect to the starting point.
-- How much the velocity of an object changes in a given time interval, regardless of direction.

Answer 1

What are your initial thoughts, on this one?

Answer 2

well i looked in the book and this is tricky lol ..I think it could be 1 or 3 I really have no idea

Answer 3

Well, this might be asking too much, but can you try to explain what acceleration is in your own words?

Answer 4

its how far something goes in a certain amount of time but the book also states something about it being a vector as well

Answer 5

It is actually how the velocity changes in a certain amount of time! That might clear up some of your confusion!

Answer 6

"How much the velocity of an object changes in a given time interval and what direction it is in" is certainly true.

Answer 7

And yes, acceleration is a vector - meaning it has both a magnitude and a direction! When you have a vector, direction is important!

Answer 8

so would the correct answer be this..How much the velocity of an object changes in a given time interval and what direction it is in. the 3rd one.. bc it states the velocity changing in the amount of time and bc its also a vector (meaning direction)

Answer 9

Dividing a quantity which is a vector by a scalar says nothing in general. consider, for ex, the pressure exerted to a body. It is nonsense to relate to the pressure a direction but it does mean in the case of the acceleration.

Answer 10

Exactly!

Answer 11

That is the definition of average acceleration, at least!

Answer 12

okay so it has nothing to do with how far

Answer 13

No. the definition is still stable even if the time difference is considerably small....

Answer 14

Nope, not at all, @pretty27 ! An object can go on forever with no acceleration if it has a velocity!

Answer 15

wait a second that just confused me can you make that clearer please?

Answer 16

so if it has a velocity but the acceleration stays the same it can go on forever but the distance has nothing to do with acceleration ?

Answer 17

I guess I was confusing...
The change in distance per time doesn't tell you what the acceleration is.

Answer 18

ohh acceleration is just velocity changing over time and with direction (vector)

Answer 19

For any object, it's motion depends on things like velocity and acceleration if it has them. But you can't tell what the acceleration is just by the change in distance per time!

Answer 20

Right! When you think acceleration, you think velocity change per time change! That is correct!

Answer 21

okay thank you so much!

Answer 22

Now, velocity has direction, so acceleration will also. Like with a falling rock. First the velocity is \(0\), then maybe \(19.6\) meters per second after \(2\) seconds. The change from \(0\) to \(-19.6\) is \(-19.6\) meters per second, and the change in time is \(2\) seconds. So the change in velocity divided by the change in time is \(\dfrac{19.6\ [m/s]}{2\ [s]}=9.8\ [m/s^2]\). I chose my numbers to make the rock fall with just gravity! :)

Answer 23

Ah! Wait...

Answer 24

\(\dfrac{-19.6\ [m/s]}{2\ [s]}=-9.8\ [m/s^2]\)

Answer 25

I forgot the negatives, which was the whole point! You see that acceleration has direction, then! :) Just a small example.

I guess that was the last one. Take care! :)

Answer 26

thank you so much for your hepl..see you soon, hopefully you will be on later this week

Answer 27

help*

Answer 28

Haha, I like to get on a couple times a week if possible! :)

Answer 29

okay thank you and talk to you soon more about physics! =D

Answer 30

Cool! Sounds fun :) Take care until then.