95.9k views
5 votes
A single, non-constant force acts in the x direction on an object of mass m that is constrained to move along the x-axis. As a result the object\'s position as a function of time is:x(t)=P+Qt+Rt^3How much work is done by this force from t = 0 s to final time T? Express your answer in terms of P, Q, R, m, and T.

User Scana
by
5.4k points

1 Answer

4 votes

Answer:

Work done is given as


W = (1)/(2)m(2Q + 3RT^2)(3RT^2)

Step-by-step explanation:

As we know that the position of object is given as


x(t) = P + Qt + Rt^3

now we know that rate of change in position of object is known as velocity

so we have


v = (dx)/(dt)


v = Q + 3Rt^2

now we have

initial speed at t = 0


v_i = Q

at t = T final speed is given as


v_f = Q + 3RT^2

now work done is change in kinetic energy


W = (1)/(2)m(v_f^2 - v_i^2)


W = (1)/(2)m[(Q + 3RT^2)^2 - Q^2]


W = (1)/(2)m(2Q + 3RT^2)(3RT^2)

User Richard Erickson
by
5.9k points