Making the Light Final Exam Review

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SUMMARY

The discussion focuses on a physics problem involving a car traveling at a constant speed of 12 m/s approaching a traffic light 44 meters away. Given a reaction time of 1 second and an acceleration rate of 6.0 m/s², the calculations reveal that the car will travel 36 meters during the initial 2 seconds before the light turns red. However, upon correcting a mathematical error, it is established that the car will actually cover 48 meters, thus successfully passing through the light before it turns red.

PREREQUISITES
  • Understanding of kinematic equations, specifically the equation for final position.
  • Knowledge of acceleration and its impact on motion.
  • Familiarity with concepts of reaction time in driving scenarios.
  • Basic algebra for solving equations and verifying calculations.
NEXT STEPS
  • Review kinematic equations for uniformly accelerated motion.
  • Study the effects of reaction time on driving safety and decision-making.
  • Explore real-world applications of acceleration in automotive physics.
  • Practice solving similar physics problems involving motion and acceleration.
USEFUL FOR

This discussion is beneficial for students studying physics, particularly those focusing on kinematics, as well as educators looking for practical examples to illustrate motion concepts.

charan1
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Homework Statement


Making the light. While traveling in your car at a constant 12 m/s, you notice a traffic light 44 m in front of
you turn yellow. You know that the light will turn red in 3.0 seconds, and that you can speed up at a rate of 6.0
m/s/s. You’re also aware that it takes you 1.0 second to actually step on the gas and begin speeding up at that
rate. Will you make it through the light before it turns red?


Homework Equations


xf=xi+Vi(delta T)+(.5)a(Delta T)^2

The Attempt at a Solution



In the one second delay because of reaction time the car travels 12 meters corresponding to the 12m/s velocity so xi=12m

xf=12m + (12m/s)(2s) + (.5)(6m/s/s)(2^2)
xf=36m

36m<44m to the light so the car will not make the light!
 
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charan1 said:
xf=12m + (12m/s)(2s) + (.5)(6m/s/s)(2^2)
xf=36m
Redo that calculation.
 
Ah math error kills thank you.

48m>44m car will make the light!
 

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