Help a highschooler with physics homework?

AI Thread Summary
The discussion revolves around a physics homework question involving vectors, specifically using I and J axes instead of traditional X and Y. The problem involves calculating the magnitude of a bike rider's velocity given as v=32m/s I + 12m/s J, leading to a magnitude of approximately 34.18m/s. To find the total distance traveled over 120 seconds, the speed is multiplied by time, resulting in a distance of 4101.6 meters. The conversation highlights the importance of understanding the relationship between speed, time, and distance in physics. Overall, the participants engage in clarifying the concepts of vector magnitude and distance calculation.
phantomcow2
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We just started vectors today and introduced the I and J axes. He insists we use I and J instead of X and Y, that's okay.

So basically here is the question asked:

A person riding a bike has a velocity v=32m/s I + 12m/s J. Determine the magnitude of hte velocity and hte bikes direction. Determine the total distance traveled by the person on the bike after 120 seconds.

SO my first step I would think is to draw quadrant 1 of an XY plane. Is the direction northeast? I would imagine this is the case because there is no mention of any negative velocities, so quadrant 1 is + in both axes.
TO determine the magnitude of velocities...
Do I simply draw a right triangle, with point (0,0) as the vertex with a 90 degree? Move up 32 in the I, and 12 in hte J?
Then use A^2+B^2=C^2 to find the hypotenuse? The hypotenuse being the magnitude?

I THINK that part I have right. BUt it is the total distance that stumps me, can somebody give some insight?
 
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You're correct about how to find the magnitude of the velocity.

Keep in mind that "the magnitude of the velocity" is a fancy way of saying "speed." Once you've found the speed, just multiply it by time to get distance.

- Warren
 
oooh, that threw me off. Speed makes it all come together in my mind :). Well now, I get 34.18m/s as a magnitude of velocity. So x 120 and 4101.6m

Thanks! I will have more questions to come tomorrow I am SURE
 
Excellent homework post. By the way, there's a forum dedicated to those somewhere around here...
 
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