Answer:
t = 2.96 s
Explanation:
Since the two stones hit the water at same instant of time
so we will have
[tex]d =vt + \frac{1}{2}gt^2[/tex]
here we know that
d = 47 m
v = 1.4 m/s
[tex]g = 9.81 m/s^2[/tex]
[tex]d = 1.40 t + \frac{1}{2}(9.81) t^2[/tex]
now by solving above equation for d = 47 m
t = 2.96 s