What was the car's velocity at t=0?

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A car accelerates at 1.75 m/s² and passes two marks 30.3 m apart at t=3.80 s and t=5.15 s. The average velocity over this interval is calculated to be 22.4 m/s. The discussion focuses on determining the initial velocity at t=0, with participants exploring how to relate average speed to initial and final velocities. It is noted that, under constant acceleration, the average speed can be expressed as the mean of the initial and final speeds. The conversation emphasizes the importance of understanding the timing of average speed in relation to the car's motion.
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Homework Statement


A car accelerates at 1.75 m/s2 along a straight road. It passes two marks that are 30.3 m apart at times t=3.80 s and t=5.15 s. What was the car's velocity at t=0?


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The Attempt at a Solution


Im actually not quite sure how to approach this question. Is there some way that i can find the velocity at the beginning of the time interval that is given?
 
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What is the average speed over the interval from 3.8s to 5.15 s?

exactly when does the car have this average speed?
 


the average velocity over that time interval is 22.4 m/s. but I am not sure what you mean by:
willem2 said:
exactly when does the car have this average speed?
 


indietro said:
the average velocity over that time interval is 22.4 m/s. but I am not sure what you mean by:

if the car goes has speed v_i at the start of the interval and v_f at
the end of the interval, its average speed is (v_i + v_f)/2. The speed at _______
is also (v_i + v_f)/2. (with constant acceleration)
 


so the middle of the interval (4.48s) would also have the velocity of 22.4 m/s ??
 
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