help me please urgently needed
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Answer:
(i)
(ii) 10s
Explanation:
u=144km/h=(144× 5/18) m/s=40m/s
v=0
s=200m
By third equation of motion, v ²= u²+ 2as
0=(40)²+ 2a(200)
−1600=400a
a=−4m/s²
Now, by first equation of motion, v=u+at
0=40+(−4)(t)
−40=−4t
t=10sec