Answer
She should stop.
Work Step by Step
The car’s initial speed is 9.722 m/s.
Consider if she tries to stop. With the acceleration of the car, $-5.8m/s^2$, can she stop the car within a distance of 28m? Use equation 2–11c.
$$0^2=(9.722m/s)^2+2(-5.8m/s^2)\Delta x$$
$$\Delta x=\frac{-(9.722m/s)^2}{2(-5.8m/s^2)}=8.15m$$
Yes, the car can stop in a little over 8 meters.
Now consider if she tries to cross the intersection. Can she reach the other side, i.e., travel 43 m, in the 2.0 seconds before the light turns from yellow to red? Find the acceleration.
$$a=\frac{65km/h-45km/h}{6.0s}\frac{1m/s}{3.6km/h}=0.9259m/s^2$$
Next, apply equation 2–11b to find the distance traveled in 2.0 s.
$$x-x_0=v_0t+0.5at^2=(9.722m/s)(2.0s)+0.5(0.9259m/s)(2.0s)^2=21.3m$$
No, she won't be able to cross the intersection before the light turns red.
