Posted by zianna on .
An automobile starts from rest and 110
ft attains a speed of 30 mi/h. In what time has it traveled this distance and the is the acceleration?
when is the acceleration of the object positive and negative?

physics 
Elena,
v=at
=>a=v/t,
s=at²/2=v t²/2t=vt/2.
t=2s/v.
positive