- #1

dramallama

- 3

- 0

## Homework Statement

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?

## Homework Equations

x=x

_{0}+V

_{0}t+1/2at

^{2}

## 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!