Acertain car can accelerate from rest to 70km/h in 7 seconds. find the cars average acceleration

A= (70-0)/7
a=10 km/hr/sec

10 km/hr = 10 km*100 m/km/(1 hr*3=600 sec/hr)=25/9 m/sec

a= 25/9 m/sec/sec

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First: we have to express the units of velocity in m/s
70 km/h=70 km/h(1000 m/km)(1h/3600 s)=19.4444m/s=19.44 m/s

average acceleration= (final velocity -initial velocity)/ time
average acceleration=(19.44 m/s - 0 m/s)/7 s≈2.78 m/s²

the cars average acceleration would be: 2.78 m/s²

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