A car is travelling at 20 km/h, it speeds upto 60 km/h in 6 seconds. What is its acceleration?
Here, Initial speed, uu = 20 km/h =20×1000 m60×60 s=20×1000 m60×60 s =5.55m/s =5.55m/s …(1) Final speed, vv= 60 km/h =60×1000 m60×60 s=60×1000 m60×60 s = 16.66 m/s …(2) Acceleration, aa = ? (To be calculated) And, Time, tt = 6 s We know that : v=u+atv=u+at So, 16.66=5.55+a×6a×6 6a=16.66−5.556a=16.66-5.55 6a=11.116a=11.11 a=11.116a=11.116 Thus, Acceleration, aa = 1.85 m/s2s2.
Initial velocity = u = 20 km/h = 20×518=509 m/s Final velocity = v = 60 km/h = 60×518=503 m/s Time = t = 6 s Step 2, Finding the acceleration Using the first equation of motion we know, v=u+at Putting all the values 503=509+a×6 After solving a=5027 m/s2 Hence the acceleration is a=5027 m/s2
