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a car accelerates from standing start and reaches a velocity if 18m/s after 6 seconds. calculate its acceleration |
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Answer» ar STARTS from rest. Final velocity of car = 18 m/s Time = 6 seconds.To find ACCELERATION of car after 6 seconds.SolutionAs here, the car starts from rest so the initial velocity of car will be 0.⇒ Initial velocity (u) = 0 m/s⇒ Final velocity (v) = 18 m/s⇒ Time (t) = 6 seconds.Equation of motion used :⇒ a = (v - u)/tPutting VALUES here :⇒ a = (18 - 0)/6⇒ a = 18/6⇒ a = 3 m/s²Therefore,Acceleration of car = 3 m/s²____________________Additional informations :Derivation of the equation [a = (v - u)/t] :We KNOW equation of motion :⇒ v = u + at⇒ at = v - u⇒ a = (v - u)/tMore equations of motion :⇾ v² - u² = 2as⇾ s = ut + ½ at²⇾ v - u = at |
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