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

1. If you are driving 70 mi/hr and you look to the side for 2 seconds, how far did you travel during this inattentive period?

2. A pilot determines that his plane can accelerate at a rate of 10,000 mi/hr². If the runway is .5 miles long and he must be traveling at 100 mi/hr in order to leave the ground, should he attempt to take-off?

3. A baseball is hit straight up into the air with a speed of 25 m/s. How high does it go and how long is it in the air?

2. Relevant equations

x=Vot+1/2at²

v=Vo+at

V² =V² o+2ax

acceleration due to gravity: g=9.8 m/s²

Everything is in absence of air resistance and any other outside forces.

x=distance covered

v=initial velocity

t=time

a=acceleration

v=speed or velocity

units=m/s²

The little "o"s next to the Vs are just initial velocity, if there is no inition velocity (starting at 0) then that part of the equation can be marked out.

3. The attempt at a solution

1. Here I am somewhat confused on which equation to choose, it can't be the second one because I am measure distance (x). I'll go with the first one.

x=Vot+1/2at²

X=(70 miles/hr)(2s)

Because there is no acceleration I am guessing I mark that part of the equation out.

Now I will attempt to convert for like units...

I really have no idea what I'm doing

2. I have notes for this, I'm just having trouble understanding them. The basic question is what is X when the plane reaches 100 mph.

V² =Vo² +2ax

100/2a=2ax/2a

100/2a=x

100/2(10,000 mi/hr² =.5mile

3. I have notes for this one as well. I think in class we went over 2 ways of doing it, one easy, one hard. Is it that I can just move the decimal place over in the 25 m/s and multiply it by two?

example: 25 m/s, so 2.5 x 2 (multiply by 2 for time up and time coming down)

Thanks for helping on any of these.

-Michael

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# Homework Help: 3 basic Sports & Physics problems

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