Simple Physics Problem: Finding c in a Particle's Position Equation at t = 3.0 s

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To find the constant c in the particle's position equation, the second derivative of the position function is calculated to determine acceleration, yielding a = 2c - 13.2t. By substituting t = 3 into the acceleration equation, the expression becomes 2c - 39.6. Using Newton's second law, the force equation F = MA is applied, where the force is given as 36 N and the mass is 1.2 kg. This leads to the equation 36 = (1.2)(2c - 39.6), which can be solved to find the value of c. The discussion focuses on correctly applying physics principles to derive the constant from the given parameters.
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Homework Statement



A 1.2 kg particle moves along an x axis, being propelled by a variable force directed along that axis. Its position is given by x = 3.0 m + (4.0 m/s)t + ct2 - (2.2 m/s3)t3, with x in meters and t in seconds. The factor c is a constant. At t = 3.0 s, the force on the particle has a magnitude of 36 N and is in the negative direction of the axis. What is c?

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The Attempt at a Solution




I double dif. to get a = 2c-13.2t and plug in t = 3 => 2c-39.6 right? F=MA so its 36 = (1.2)(2c-39.6)?
 
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