2. 1D Motion / Kinematics

Which of the following best describes positive $a$?

Which two controls on a car are primarily responsible for causing a change in $v$?

A cheetah accelerates from $15\text{m/s}$ to $30\text{m/s}$ in $3.0\text{s}$. What is the cheetah's acceleration?

An object moves along a straight line and its velocity vs. time graph consists of three segments: Segment A (velocity increases from $0$ to $5 m/s$ from $t=0$ to $t=2 s$), Segment B (velocity remains constant at $5 m/s$ from $t=2 s$ to $t=4 s$), and Segment C (velocity decreases from $5 m/s$ to $0$ from $t=4 s$ to $t=6 s$). During which segment(s) is the object speeding up?

Which of the following best explains why quick acceleration can increase fuel consumption by $2\text{ miles per gallon;}$?

Starting from rest, a car accelerated to 20m/s in 4s. What was the magnitude of the car's constant acceleration?