What is the significance of position equation of a function?
This tells us where the particle is at different values of t (time)
What is velocity?
This is the change of the position function over time.
The velocity of a particle is the rate at which its position changes with respect to time, expressed as both its speed and its direction of motion.
v=dx/dt
What is acceleration?
This is the change of velocity over time.
A particle P moves on the number line. The graph s=f(t) shows the position of P as a function of time t.

a. When is P moving to the left?
b. When is P moving to the right?
c. When is P at rest?
P moving to the left (2, 3) and (5, 6)
P moving to the right (0, 1)
P at rest (1, 2) and (3, 5)
What is
x(t)?
This is the position function.
What happens when
v(t)>0
on a horizontal line (where is the particle moving)
To the right (or in the positive direction).
What is
x'(t)?
This is what v(t) is equal to.
The figure shows the velocity
v=(ds)/dt=f(t)
of a body moving along a coordinate line in meters per second.

a. When does the body reverse direction?
b. When is the body moving at a constant speed?
c. What is the body’s maximum speed?
a. The body reverse direction t=2 and t=7.8 (velocity changes signs)
b. The body moving at a constant speed (3,4) (velocity is zero)
c. The body’s maximum speed 4m/sec
Find and explain the meaning
x(t)=t^2-2t-3
when
t=4
x(4)=5
The particle is 5 unit to the right of the origin after 4 minutes
What is x"(t) or v'(t)?
a(t)
What is the acceleration function of
x(t)=2t^4+4t^3+t^2
.
24t^2+24t+2
The data in the table gives selected values for the velocity, in meters per minute, of a particle moving along the x-axis. The velocity v is a differentiable function of time t.

At t = 0, is the particle moving to the right or left? Justify.
Left because the velocity is negative.
v(0)<0
This is the position of
x(t)=2t^3+4t^2+t
, when
t=2
The particle is 34 feet to the right of the origin after 2 minutes
x(2)=34
What is the velocity function of
x(t)=t^4 – 2t^3 – 6t^2 + 9t.
v(t) = 4t^3 – 6t^2 – 12t + 9
A particle moves along a line so that its position at any time
t>=0
is given by the function
s(t)=1/3t^3-3t^2+8t-5
where s is measured in meters and t is measured in seconds.
Find the acceleration of the particle at any time t.
a(t)=2t-6
The data in the table gives selected values for the velocity, in meters per minute, of a particle moving along the x-axis. The velocity v is a differentiable function of time t.

Use the data from the table to approximate v′(10). Explain the meaning of v'(10) in terms of the particle motion.
At 10 minutes, the particle's velocity is decreasing by 0.5 m/min^2
(v(12)-v(8))/(12-8)
v'(10)=-0.5
A particle moves along a line so that its position at any time
t>=0
is given by the function
s(t)=1/3t^3-3t^2+8t-5
where s is measured in meters and t is measured in seconds.
What is the displacement of the particle for the first 3 seconds?
s(3)-s(0)=6 meters
A particle moves along a line so that its position at any time
t>=0
is given by the function
s(t)=1/3t^3-3t^2+8t-5
where s is measured in meters and t is measured in seconds.
When is the particle at rest?
t=2 and t=4 seconds
A ball is dropped off a 1200 ft cliff. The height of the ball over time is modeled by the function
h(t)=1200-16t^2
where h is the height of the ball and 𝑡 is time in seconds.
Find
h''(3)
. Explain what it means.
h''(3)=32
At 3 seconds, the rate the ball is falling is increasing by 32 feet / second per second.
The graph represents the velocity, in feet per second, of a particle moving along the x-axis over the time interval from 𝑡 = 0 to 𝑡 = 9 seconds.

What is the average acceleration of the particle over the interval 2 ≤ t ≤4?
a(t)=(v(4)-v(2))/(4-2)
-1.5(ft)/sec^2