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Simple harmonic motion, finding displacement given time

  • Thread starter scholio
  • Start date
1. The problem statement, all variables and given/known data

mass = 1.8kg
given equation in problem x(t) = (7.40cm)cos[(4.16s^-1)t - 2.42]
*when i tried solving i converted 7.40cm to 0.074m

find the position of the mass at t = 1.00s

2. Relevant equations

x(t) = (7.40cm)cos[(4.16s^-1)t - 2.42]

3. The attempt at a solution

i've been working on this problem for a while, i haven't been able to get the correct answer, even when i made sure to check units and make necessary unit conversions. i made sure my units were in radians (within the cosine) but it keeps yielding the wrong answer, i was able to find velocity and acceleration from the given equation, just not position.

i thought this problem would be just plug and chug, when i stuck t=1.00s it still hasn't given me the correct answer, i got -0.01 and 0.074, both were incorrect

EDIT sorry for double posting - actually was kinda correct the first time, it was just very picky with sig figs, i initially entered -0.01 which was incorrect, the actual answer was -0.0125

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