Posted by **Anna** on Sunday, January 22, 2012 at 12:14pm.

A car stops for a red ligth. The light turns green and the car moves for 3 seconds at a steadily increasing speed. During this time, it travels 20 meters. The car then travels at a constant speed for another 3 seconds for a distance of 30 meters. Finally, when approaching another red light, the car steadily slows to a stop during the next 3 seconds in 15 meters. Create equations with respect to time for the position and velocity of the car at each segment.

- physics -
**Henry**, Tuesday, January 24, 2012 at 4:59pm
d1 = 0.5a*t^2 = 20 m.

0.5a*3^2 = 20,

4.5a = 20,

a = 4.44 m/s^2.

V = at = 4.44 m/s^2 * 3 s=13.32 m/s.

V = d2/t = 30/3 = 10 m/s.

a = (Vf-Vo)/t = (0-10) / 3=-3.33 m/s^2

d3 = Vo*t + 0.5a*t^2 = 15 m.

10*3 + 0.5a*3^2 = 15,

30 + 4.5a = 15

4.5a = 15-30 = -15,

a = --3.33 m/s^2.

## Answer This Question

## Related Questions

- physics - A car is stopped for a traffic signal. When the light turns green, the...
- PHYSICS - You are driving your car and the traffic light ahead turns red. You ...
- Physics - Two cars start from rest at a red stop light. When the light turns ...
- science - a car is stopped at a traffic light, which then turns green. The car ...
- physics - Two cars start from rest at a red stop light. When the light turns ...
- physics - please somebdy help me solveing this. Two cars start from rest at a ...
- AP Physics - 1. A car is traveling down the road at a constant speed of 11 km/h...
- physics with 6 questions - Two cars start from rest at a red stop light. When ...
- physics - Two cars start from rest at a red stop light. When the light turns ...
- Physics - To save fuel, some truck drivers try to maintain a constant speed when...

More Related Questions