You can put this solution on YOUR website! starting at 0km/h ending at top speed of 5km/h how far would I travel in 4 seconds
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If you mean you accelerate from 0 to 5 km/hr in 4 seconds, then
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5 km/hr = 25/18 meters/sec
accel = 5/4 = 25/72 m/sec/sec
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s = at^2/2 = (25/72)*4^2/2 meters
s = 50/9 meters