Question

The motion of a particle is defined by the relation x = 1.5t^4 - 30t^2 + 5t + 10, where x and t are expressed in meters and seconds, respectively. Determine the position, the velocity, and the acceleration of the particle when t = 4 s.

Answer 1

find the velocity and acceleration by taking the derivative, then substitute t = 4

Answer 2

x(t) = 1.5t^4 - 30t^2 + 5t + 10 position
x'(t) = 6t^3 - 60t + 5 velocity
x''(t) = 18t^2 - 60 acceleration

substitute t = 4 for each ~

Answer 3

i got negative (-) 66 for the position. what does it mean?

Answer 4

then it's going backward :s

Answer 5

yea. :>