An OpenStudy user's speed is 40 medals per day and his acceleration is 2 medal/day^2. If it takes 4,500 medals to reach the Legend rank, how many days will it take for him to reach the rank?

Question

anonymous · Answer

lol in first

anonymous · Answer

wrong group

lgbasallote · Answer

isnt it math?

anonymous · Answer

What is his/her initial medalage?  does he/she start from 0?

anonymous · Answer

physics

lgbasallote · Answer

yup 0

lgbasallote · Answer

but isnt this an ordinary math problem too?

lgbasallote · Answer

i mean the basic concepts still come in play

anonymous · Answer

its both, physics and math.Arguably physics is nothing without math though :)

lgbasallote · Answer

lol can we just teach me how to solve this? :p

anonymous · Answer

well first of all, his acceleration cant be 2 medals/day 

a = v / t

since you postulated that v  = 40 per day

a = 40 per day

because a = delta V / delta t

lgbasallote · Answer

but my book says 50 days o.O

anonymous · Answer

I would consider it an initial velocity.  Its like saying a car is going at 40 ft/s, and accelerating at 2 ft/s^2.

lgbasallote · Answer

yeah that'swhat i think too

anonymous · Answer

To solve the problem use the formula:$$d = x_0+v_0t+\frac{1}{2}at^2$$Set d to 4500, intial position to 0, intiial velocity to 40, and acceleration to 2.  Solve for t.

lgbasallote · Answer

so 4500 = 40t + t^2?

anonymous · Answer

yep

lgbasallote · Answer

hmm yep i think that gives 50thanks