car traveling at $4.0 \mathrm{~m} / \mathrm{s}$ has a constant acceleration of $2.0 \mathrm{~m} / \mathrm{s}^{2}$ in the same direction as the velocity. After 3.0 seconds, the magnitude of the average velocity during the acceleration is
A) $5.0 \mathrm{~m} / \mathrm{s}$.
B) $9.0 \mathrm{~m} / \mathrm{s}$.
C) $7.0 \mathrm{~m} / \mathrm{s}$.
D) $11 \mathrm{~m} / \mathrm{s}$.
E) 13.

Question

Quizplus · Accepted Answer

The average velocity during constant acceleration is the average of the initial and final velocities. Initial velocity $v_i = 4.0 \, \mathrm{m/s}$, final velocity $v_f = v_i + at = 4.0 + 2.0 \times 3.0 = 10.0 \, \mathrm{m/s}$. Average velocity = $(v_i + v_f) / 2 = (4.0 + 10.0) / 2 = 7.0 \, \mathrm{m/s}$.

Car Traveling At 4.0 m/s4.0 \mathrm{~m} / \mathrm{s}4.0 m/s Has a Constant Acceleration Of

Car Traveling At $4.0 \mathrm{~m} / \mathrm{s}$ Has a Constant Acceleration Of