# Physics

posted by .

A person driving her car at 54 km/h approaches an intersection just as the traffic light turns yellow. She knows that the yellow light lasts only 2.0 s before turning to red, and she is 30 m away from the near side of the intersection. The intersection is 15 m wide. Her car's maximum deceleration is -6.6 m/s2, whereas it can accelerate from 54 km/h to 70 km/h in 4.8 s. Ignore the length of her car and her reaction time.

If she hits the brakes, how far will she travel before stopping?

If she hits the gas instead, how far will she travel before the light turns red?

Should she try to stop, or should she speed up to cross the intersection before the light turns red?

• Physics -

yes

• Physics -

n,m,m,,mmklm

## Similar Questions

1. ### Physics

You are driving to the grocery store at 20 m/s . You are 110m from an intersection when the traffic light turns red. Assume that your reaction time is 0.50s and that your car brakes with constant acceleration. _ How far are you from …
2. ### Physics

You are driving to the grocery store at 11.9m/s. You are 169.0m from an intersection when the traffic light turns red. Assume that your reaction time is 0.730s and that your car brakes with constant acceleration. How far are you from …
3. ### Physics

A 15.0 m long truck traveling at 40.0 mph has a braking capability of 5.00 m/s2 from this speed. It is approaching a 10.0-m wide intersection with a traffic light that is turning yellow. (a) What is the minimum distance the truck can …
4. ### physics

A person driving her car at 56km/hr approaches an intersection just as the traffic light turns yellow. She knows that the yellow light lasts only 20.s before turning to red, and she is 30m away from the near side of the intersection. …
5. ### science

When the front of a 5.0 m long bus traveling at a constant speed of 20 m/s is 55 m away from an intersection, the traffic light turns yellow. It will take 3.0 s before the traffic light turns red. The driverâ€™s reaction time is 0.25 …
6. ### Science Help

1.) A rail gun uses electromagnetic energy to accelerate objects quickly over a short distance. In an experiment, a 2.00 kg projectile remains on the rails of the gun for only 2.10x10-2 s, but in that time it goes from rest to a velocity …
7. ### Physics

A car is driving at a speed of 66.0 km/h toward an intersection just as the light changes from green to yellow. The driver has a reaction time of 0.750 s and the magnitude of the braking acceleration of the car is 5.50 m/s2.Find the …
8. ### Physics

A person driving her car at 45km/h approaches an intersection just as the traffic light turns yellow. She knew that the yellow light lasts only 2s before turning red,and shi is 28m away from the near side of the intersection. Should …
9. ### Physics

You're approaching an intersection at 50 km/h (13.9 m/s ). You see the light turn yellow when you're 35 m from the intersection. Assume a reaction time of 0.6 s before braking begins and a braking acceleration of -3.0 m/s2. A) will …
10. ### applied mechanics

a motorist driving his car at a speed of 72km/hr observes that the traffic lights ahead of him turns red if he comes to a halt at the traffic light 5seconds starting from first find the distance of the car from the light when the motorist …

More Similar Questions