(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Just when a Frisbee passes over the head of a student at a speed of 4m/s and decelerating at a rate of 1.5 m/s^{2}, she starts to run accelerating at a rate of 1 m/s^{2}. [neglect vertical motion of Frisbee]

a)How long will it take the student to catch the Frisbee?

b) If instead of accelerating the student were able to run at a constant speed of 2 m/s as soon as the Frisbee passes her head how far would she have to run to catch it?

2. Relevant equations

x=x_{0}+V_{0}t+1/2at^{2}

3. The attempt at a solution

So for part a, I figured if I made both x_{frisbee}and x_{student}equal to each other I could solve for t

x_{frisbee}=0+4t+(0.5)(-1.5)t^{2}

x_{student}=0+0t+(0.5)(1)t^{2}

0.5t^{2}=4t+0.75t^{2}

t=0s t=3.2s

And something similar for part b:

x_{frisbee}=0+4t+(0.5)(-1.5)t^{2}

x_{student}=0+2t+(0.5)(0)t^{2}

4t+(0.5)(-1.5)t^{2}=2t

t=0s t=2.7s

x=(2m/s)(2.7s)=5.4m

I just wanted to know if I got these right. Thanks!

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# Homework Help: 1D Motion

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