question 16\na car is stopped at a red traffic light. when the light turns to green, the car has a constant…

question 16\na car is stopped at a red traffic light. when the light turns to green, the car has a constant acceleration and crosses the 9.10 - m intersection in 2.86 s. what is the magnitude of the cars acceleration?\n7.36 m/s²\n9.80 m/s²\n2.98 m/s²\n1.77 m/s²\n2.23 m/s²
Answer
Explanation:
Step1: Identify the kinematic - equation
The car starts from rest ($v_0 = 0$), and the kinematic equation $x=v_0t+\frac{1}{2}at^{2}$ is used. Since $v_0 = 0$, the equation simplifies to $x=\frac{1}{2}at^{2}$.
Step2: Solve for acceleration $a$
We can re - arrange the equation $x=\frac{1}{2}at^{2}$ to solve for $a$. We get $a=\frac{2x}{t^{2}}$.
Step3: Substitute the given values
Given $x = 9.10$ m and $t = 2.86$ s. Substitute these values into the formula: $a=\frac{2\times9.10}{(2.86)^{2}}$. $a=\frac{18.2}{8.1796}\approx2.23$ m/s²
Answer:
$2.23$ m/s²