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A car starts from rest and accelerates at 5 m/s through a distance of 22,5m. How fast is it they going?Hoe long did it take to cover 22,5 m ? |
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Answer» This may help youExplanation: Avg speed × total times = total distance20×25=500Since acceleration in the 1st interval is same as DECELERATION in the 3rd interval and deceleration is from the same VELOCITY achieved after acceleration, t 1=t 3s 1= 2 1 ×5t 1 s 2=(5t 1)t 2s 3=(5t 1)×t 3− 2 1×5×t 1 2 =(5t 1)×t 1− 2 1×5×t 1 2s 1+s 2+s 3=5t 1T 2+5t 1t 2⇒5t 1 2+5t 1 2=500−−−−12t 1+t 2=25−−−−2Solving (1 ) and (2) ⇒t 1=5,t 2=15sec |
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