Position as a function of time

AI Thread Summary
The discussion centers on finding the position and velocity equations for a cart moving under a constant force on a frictionless surface. The cart starts at a position of 5.0 meters at time 0.0 seconds and reaches 49.0 meters by 2.0 seconds, with time increasing in 0.1-second increments. Participants clarify the need for equations during the force application period and emphasize the importance of showing prior attempts to solve the problem. Alexandre expresses frustration in determining the initial velocity and seeks guidance without wanting the problem solved completely. The conversation highlights the collaborative nature of problem-solving in physics.
Billmaz89
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Hi all,
I can't find a function of this data, since the cart is already in motion. Please help a noobie at physics!
Time is increasing from 0.0 to 2.0 by .1
x (in m) is 5.0 at 0.0 and 49.0 at 2.0 seconds

the cart that's moving is 5.0 kg intially traveling at some unknown velocity on a horizontal frictionless surface. Starting at t=0s, a constant force F, is applied for two seconds, after these two seconds the force is no longer applied.

so, the question is,
Find an equation for position as a function of time that fits the data. Then find an equation for the cart's velocity as a function of time.

Any help would be much appreciated!
 
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A couple of questions:

what do you mean by "Time is increasing from 0.0 to 2.0 by .1"

Do you need the equation for after the force is applied, or just while the force is applied?

Also, what have you tried doing so far? We can only help you if you show a sincere effort in solving the problem yourself. Let us know!


Alexandre Colavin
 
In increments of 0.1, presumably.
 
in increments of .1 until it reaches 2.0, yes, and I've been going through given equations to try to find the velocity, and the amount of force applied. But I can't find an equation that doesn't require the unknown initial velocity so I'm kind of stuck just looking at equations. I'm not asking for the problem done for me, I just need to be pointed in the correct direction.and just while the force is applied is my guess, it wasn't asking anything after the force is done I'm pretty sure.
 
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