Answers

2014-05-08T09:44:45+05:30
We have,
distance (s) = ?
Time = (t) = 4 seconds
Acceleration (a) = 2.5m/s²
Initial velocity (u) = 0 (the girl started the race)
So, by using second equation of motion we have,
s = ut +  \frac{1}{2} at²
s = 0*4 +   \frac{1}{2}*2.5*4*4
s = 0 + 20
s = 20
So, the distance travelled by the girl is 20 m.


 
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2014-05-11T14:35:51+05:30
From second equation of motion,
S=ut+1/2at^2
S=0*4+1/2*2.5*4^2
S=1/2*2.5*16
S=2.5*8
S=20 m
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