Calculating Speed from Acceleration and Time

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To calculate speed from acceleration and time, multiplying the acceleration (3.47 m/s²) by the time (5 seconds) gives a speed of 17.4 m/s, which is correct in this scenario. The kinematic equation v = u + at can be used, where u is the initial speed (0 m/s since the car starts from rest). It's important to ensure the initial conditions are correctly understood; the formula applies only when starting from rest. Therefore, the method used here is valid for the given problem. Understanding the context of the motion is crucial for accurate calculations.
wakejosh
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can I just multiply 3.47 m/s/s by 5 seconds to get my speed after that amount of time? for example:

. A European sports car dealer claims that his car will accelerate
at a constant rate from rest
to a speed of 100 km/hr (28 m/s) in 8.00 s. What is the speed
after the first 5.00 s of
acceleration?

a.44.4 m/s b. 34.7 m/s c. 28.7 m/s d. 17.4 m/s e. 8.7
m/s


First I find the acceleration to be 3.47 m/s^2 now can i just times by 5? If so i get 17.4 m/s Is this correct?
 
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yes that is correct

if u are in doubt you can always look at what you're given and your kinematic equations to get your answer
 
v=u+at
You are right in this context but make sure you have an accurate bearing of your question. It would not have been correct if the car did not start from rest.
 
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