Questions: A person travels 75.0 m with a final velocity of 10.0 m / s over 10.0 s. What is the person's acceleration? a=[?] m / s^2
Transcript text: A person travels 75.0 m with a final velocity of $10.0 \mathrm{~m} / \mathrm{s}$ over 10.0 s .
What is the person's acceleration?
\[
\mathrm{a}=[?] \mathrm{m} / \mathrm{s}^{2}
\]
Solution
Solution Steps
Step 1: Identify the known variables
We are given the following information:
Final velocity, \( v_f = 10.0 \, \text{m/s} \)
Time, \( t = 10.0 \, \text{s} \)
Distance traveled, \( d = 75.0 \, \text{m} \)
Step 2: Use the kinematic equation to find initial velocity
We use the kinematic equation:
\[
d = v_i t + \frac{1}{2} a t^2
\]
where \( v_i \) is the initial velocity and \( a \) is the acceleration. We need to find \( v_i \) first.
Step 3: Use another kinematic equation to relate initial and final velocities
We use the equation:
\[
v_f = v_i + a t
\]
Rearranging for \( v_i \):
\[
v_i = v_f - a t
\]
Step 4: Substitute \( v_i \) into the distance equation
Substitute \( v_i = v_f - a t \) into the distance equation:
\[
d = (v_f - a t) t + \frac{1}{2} a t^2
\]
Simplify:
\[
d = v_f t - a t^2 + \frac{1}{2} a t^2
\]
\[
d = v_f t - \frac{1}{2} a t^2
\]
Step 5: Solve for acceleration \( a \)
Rearrange the equation to solve for \( a \):
\[
d = v_f t - \frac{1}{2} a t^2
\]
\[
75.0 = 10.0 \times 10.0 - \frac{1}{2} a \times 10.0^2
\]
\[
75.0 = 100.0 - 50.0 a
\]
\[
50.0 a = 100.0 - 75.0
\]
\[
50.0 a = 25.0
\]
\[
a = \frac{25.0}{50.0}
\]
\[
a = 0.5000 \, \text{m/s}^2
\]