Travel time for an accelerating car

AI Thread Summary
The user calculates the total travel time for a car accelerating to a speed limit of 50 km/h, maintaining that speed for 30 seconds, and then decelerating to a stop. The acceleration phase takes 2.8 seconds, followed by 30 seconds of constant speed, and the deceleration phase takes 4.6 seconds. The total time calculated is 37.4 seconds. The user expresses satisfaction with this result and seeks confirmation on its accuracy. Overall, the calculations appear to be correct based on the provided parameters.
Irukandji
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Hi guys,

i hope i find the right Sub-Forum. Can you please tell me if i calculated it right.

A car speed's up with 5 m/s² to a speed limit of 50Km/h. After it arrived the speedlimit it drives for 30s with the speed of 50km/h. After that it break with a negative acceleration 3.0m/s² to stop the car. How many time it need from start to stop?

My calculation:

(50km/h) : 3,6 = 13,9 m/s

first step:

t = v/a
t= 13,9m/s : 5m/s² = 2,8s

second:

t= 30s

third:

t= v/a =13,9m/s : 3m/s² = 4,6s

Now i add this

t1 + t2 +t3 = 2,8s + 30s + 4,6s = 37,4s

My result is 37,4s. Is this right or iam totaly wrong?
 
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Looks good to me.
 
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Thanks this makes me happy.
 
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