when the light turns green a driver stopped at a traffic light accelerates and a

Question

when the light turns green a driver stopped at a traffic light accelerates and after 12 s the car is traveling at 45 mi/hr, the driver continues at this speed, how long will it take the driver to travel 8 mi from the traffic light? when the light turns green a driver stopped at a traffic light accelerates and after 12 s the car is traveling at 45 mi/hr, the driver continues at this speed, how long will it take the driver to travel 8 mi from the traffic light? when the light turns green a driver stopped at a traffic light accelerates and after 12 s the car is traveling at 45 mi/hr, the driver continues at this speed, how long will it take the driver to travel 8 mi from the traffic light?

Explanation / Answer

apply the Kinetic equation V = at

so

a = V/t

where a is accleration

t is time = 12 s

speed V = 45 mph = 45* 0.4470 = 20.115 m/s

so

a = 20.115/12

a = 1.676 m/s^2

so

now use S = 0.5 at^2

so

t^2 = 2S/a

1 mile = 1609.34 m

t^2 = (2* 8 * 1609.34)/1.676

t^2 = 15363.62

t = 124 secs

Related Questions

Navigate

• Browse (All)
• Browse W
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.