Vector Expression of x & y as Function of Time: Unit Vectors i & j

Thread starter silent bob
Start date Feb 18, 2007
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Expression Vector

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To express the position as a function of time using unit vectors i and j, the equations x = (12 m/s)t and y = (2.55 m/s)t - (4.9 m/s^2)t^2 can be combined. The position vector can be written as r(t) = x i + y j. Substituting the expressions for x and y, the position vector becomes r(t) = (12 m/s)t i + [(2.55 m/s)t - (4.9 m/s^2)t^2] j. This formulation clearly illustrates the motion in both the x and y directions as functions of time. The final expression captures the vector representation of the position in a two-dimensional space.

Feb 18, 2007

silent bob

how would i write x= (12 m/s)t , y= (2.55 m/s)t-(4.9 m/s^2)t^2 as a function of time using the unit vectors i and j?

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Feb 26, 2007

Doc Al

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silent bob said:

how would i write x= (12 m/s)t , y= (2.55 m/s)t-(4.9 m/s^2)t^2 as a function of time using the unit vectors i and j?

Hint: The position is x i + y j

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