Non-Constant Acceleration Problem

Join the discussion
Ask a follow-up here, or get your own question answered by working scientists, mathematicians and engineers — people, not an autocomplete.
Real named experts · corrections over time · the nuance an AI answer skips
5 replies · 2K views
Jewelz
Messages
8
Reaction score
0

Homework Statement


A new Tesla is designed that can perform a non-constant acceleration for 10 seconds of motion. The magnitude of the acceleration is given as a(t) = 1 m/s4t2

Starting from rest, how far does the car travel over this 10 second interval?

Homework Equations


This is what is making the question difficult for me. I am unsure what equations to use with a non-constant acceleration.

The Attempt at a Solution


I tried solving it manipulating the constant velocity and acceleration equations, but everything I have tried has been wrong. Even if someone could point me in the right directions equations wise, I'm sure that would help me a lot.

Thanks
 
Physics news on Phys.org
Hi, you can find the velocity function respect to ##t## that is ##v(t)=\int_{0}^{t} a(s)ds## and after the space ##x(t)=\int_{0}^{t}v(s)ds##, put ##t=10 s## in ##x(t)## ...
Ssnow
 
Jewelz said:

Homework Statement


A new Tesla is designed that can perform a non-constant acceleration for 10 seconds of motion. The magnitude of the acceleration is given as a(t) = 1 m/s4t2

Starting from rest, how far does the car travel over this 10 second interval?

Homework Equations


This is what is making the question difficult for me. I am unsure what equations to use with a non-constant acceleration.

The Attempt at a Solution


I tried solving it manipulating the constant velocity and acceleration equations, but everything I have tried has been wrong. Even if someone could point me in the right directions equations wise, I'm sure that would help me a lot.

Thanks

Your input is hard to read; I assume you mean ##a = k t^2,## where ##k = 1 m/s^4.##

Anyway, you get velocity ##v## by integrating ##a## with respect to ##t##, and then you get position by integrating ##v##. No amount of manipulation of the constant-acceleration formulas can do what you need.
 
Last edited:
Ray Vickson said:
Your input is hard to read; I assume you mean ##a = k t^2,## where ##k = 1 m/s^4.##

Anyway, you get velocity ##v## by integrating ##a## with respect to ##t##, and then you get position by integrating ##v##. No amount of manipulation of the constant-acceleration formulas can do what you need.
Your assumption is correct.

After integrating the acceleration function with respect to time, with the bounds of the integral from ##0## to ##t##, I obtained the function ##t^3/3## for the velocity. Integrating that, from 0 to t for the integral, I got ##t^4/12##, and plugging in ##t## (10 seconds), I obtained a final answer of 833.3m traveled.

Does this all sound correct?
 
Jewelz said:
Your assumption is correct.

After integrating the acceleration function with respect to time, with the bounds of the integral from ##0## to ##t##, I obtained the function ##t^3/3## for the velocity. Integrating that, from 0 to t for the integral, I got ##t^4/12##, and plugging in ##t## (10 seconds), I obtained a final answer of 833.3m traveled.

Does this all sound correct?

It does.
 
Jewelz said:
Your assumption is correct.

After integrating the acceleration function with respect to time, with the bounds of the integral from ##0## to ##t##, I obtained the function ##t^3/3## for the velocity. Integrating that, from 0 to t for the integral, I got ##t^4/12##, and plugging in ##t## (10 seconds), I obtained a final answer of 833.3m traveled.

Does this all sound correct?
Yes, perfect.