An object is moving along a straight line parallel to the x-axis. Its position as a function of time is given by:
x(t)=30 m−21 (ms) t+3 (ms2) t2
where the position x is in (m) and the time t is in (s).
(a) What is the object's velocity at t=0 s, 2 s, and 5 s? (enter the x-component of the velocity in m/s. Do not enter the units in the box.)
vx(t=0)=
vx(t=2)=
vx(t=5)=
(b) What is the object's acceleration at t=0 s, 2 s, and 5 s? (enter the x-component of the acceleration in m/s2. Do not enter the units in the box.)
ax(t=0)=
ax(t=2)=
ax(t=5)=
(c) At what time T is the object's velocity zero?(Enter your answer in s. Do not enter the units in the box.)
T=
What is the object's position when its velocity is zero? (Enter the x-component of the position in m. Do not enter the units in the box.)
x(T)=
(d) What is the average velocity between t1= 1.0 s and t2=3.5 s? (Enter the x-component in m/s. Do not enter the units in the box.)
v¯x,t1,t2=
(e) What is the object's average velocity between t1= 0 s and t2=7.0 s? (Enter the x-component in m/s. Do not enter the units in the box.)
v¯x,t1,t2=
(f) What is the object's average speed between t1= 0 s and t2=7.0 s? (Enter the x-component in m/s. Do not enter the units in the box.)
(g) At what time t3 does the object reverses its direction? (Enter your answer in s)
t3=