Acceleration, distance, time. help.

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Vehicle 1 travels at a constant speed of 90 mph, while Vehicle 2 accelerates from 0 to 90 mph over 17.09 seconds. To determine how far Vehicle 2 travels during acceleration and when it catches up to Vehicle 1, users suggest setting up position functions for both vehicles and solving for time. The equations involve constant acceleration for Vehicle 2 and constant velocity for Vehicle 1, leading to a quadratic equation to find the catch-up time. Discussions also mention calculating distances, with some users proposing values around 4044.8 ft and 558.46 ft for the distance traveled.
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Homework Statement



vehicle 1 is traveling at a constant speed of 90mph (132 f/s) 5 seconds before vehicle 2 begins to accelerate from 0-90 mph taking 17.09 seconds to do so. how far a distance will vehicle 2 travel while accelerating to 90mph. and how long will it take for vehicle 2 to catch up to vehicle 1 while accelerating at approximately 5.2 m/s/s or 15.6 f/s

Homework Equations



The relationship between the 2 vehicles is dependent.

what is the total distance traveled by vehicle 2 before it catches up to vehicle 1?


The Attempt at a Solution



ok, it's too hard to explain and argue at the same time, so i'll leave it at this:
find a function of position for car #1 and car #2, call them c_1(t) and c_2(t), set them equal and solve for t. what does this mean exactly?
This should help you a bit, at constant acceleration, call it a, the position of car 2 at time t is at^2/2
the first car, meanwhile is moving at a constant velocity v, so its position at time t is vt
does car 2 start from rest?
so solve vt=at^2/2 -> at^2-vt=0 -> use quadratic formula
this will give you the time t, when car 2 catches up to car 1, ?? to answer part 2 of the Q
 
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For your first question you could use the equation Vf^2 = Vi^2 + 2(a)(d) where Vf is the final velocity, Vi is the initial velocity, a is the acceleration, and d is the displacement.

For number 2, since the first car is traveling at constant speed we can label the distance it travels as d = V(t + 5) while we may use the equation df = (a)(t^2)/2 + (Vi)t + di. Equate the two and solve for the time.
 
did you get a distance of 4044.8 ft for the first part of the question?

or 558.46 ft?
 
Last edited:
anyone get an answer for this?
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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