Answer
(a) The number 2.0 is the initial position.
The number 3.6 is the initial speed.
The number 1.7 is half of the acceleration.
(b) The unit of 2.0 is meters.
The unit of 3.6 is m/s.
The unit of 1.7 is $m/s^2$.
(c) When $t = 1.0 ~s$ then $x = 0.1 ~m$
When $t = 2.0 ~s$ then $x = 1.6 ~m$
When $t = 3.0 ~s$ then $x = 6.5 ~m$
(d) The average velocity over the interval $t = 1.0 ~s$ to $t = 3.0 ~s$ is 3.2 m/s.
Work Step by Step
(a) The number 2.0 is the initial position.
The number 3.6 is the initial speed.
The number 1.7 is half of the acceleration.
(b) The units of 2.0 are meters.
The unit of 3.6 is m/s.
The unit of 1.7 is $m/s^2$.
(c) $x = 2.0 - 3.6t + 1.7t^2$
When $t = 1.0 ~s$:
$x = 2.0 ~m - (3.6 ~m/s)(1.0 ~s) + (1.7 ~m/s^2)(1.0 ~s)^2 = 0.1 ~m$
When $t = 2.0 ~s$:
$x = 2.0 ~m - (3.6 ~m/s)(2.0 ~s) + (1.7 ~m/s^2)(2.0 ~s)^2 = 1.6 ~m$
When $t = 3.0 ~s$:
$x = 2.0 ~m - (3.6 ~m/s)(3.0 ~s) + (1.7 ~m/s^2)(3.0 ~s)^2 = 6.5 ~m$
(d) average velocity = $\frac{\Delta x}{\Delta t} = \frac{6.5 ~m - 0.1 ~m}{3.0 ~s - 1.0 ~s} = 3.2 ~m/s$
The average velocity over the interval $t = 1.0 ~s$ to $t = 3.0 ~s$ is 3.2 m/s.
