Doing a linear motion lab with an inclined plane help plzzzzz

Question

anonymous · Answer

What's up.

anonymous · Answer

Well im doing this physics lab where we allowed a marble to run along a frictionless inclined plane at various distances and times

anonymous · Answer

we also had to find time square

anonymous · Answer

you looking to find acceleration?

anonymous · Answer

now its asking me to predict the shape of graph using s=1/2at^2

anonymous · Answer

with distance against time square

anonymous · Answer

and distance against time

anonymous · Answer

find the meaning of the slopes

anonymous · Answer

and plot graphs accordingly

anonymous · Answer

So here is the question, do you think that the acceleration changed as you varied the distance?

anonymous · Answer

and i am sooo lost

anonymous · Answer

no worries, we got this :) we'll go one step at a time.  So in the lab you varied the distance you rolled the marble and timed how long to get down the inclined plane, correct?  you never changed the incline or did you?

anonymous · Answer

nope

anonymous · Answer

Okay, so the first part asking you to graph distance vs. time squared:

s = 1/2a t^2
Well that looks awfully close to
y = mx +b     (remembering that b is the y intercept)

So let's break that down a bit.
For you y is the distance s
x is t^2
b would be the distance if time is zero (which should be zero)

So that puts 1/2a as your slope m

If you think 1/2a stays the same as you very the distance the marble rolls, then the relationship is linear.  If you think 1/2a changes, then it would be some more complicated relationship: quadratic, higher order polynomial etc.

anonymous · Answer

i think im getting it

anonymous · Answer

:)

anonymous · Answer

questions?

doc.brown · Answer

You are in a car.
You are going a certain speed.$$v_0$$You change your speed for an amount of time.$$t$$To a new speed.
$$v$$You accelerated.  A change in speed in some direction, or velocity, over a period of time.
$$a=\frac{v-v_0}{t}$$But velocity is distance over time km/h, m/s, are you american? mi/hr?$$v=\frac{d}{t}$$So acceleration is$$a=\frac{d}{tt}=\frac{d}{t^2}$$It's not time squared so much as it's change in velocity per second.