Answer:
Time in air = 1.89 seconds and time in water = 10.11 seconds
Step-by-step explanation:
We have to find the time duration through which it travelled in both air and water.
It had an average speed of 16 m/s in air and 3 m/s in water. Also the total distance travelled = 127 meters.
The total time of fall of the rock = 12 seconds .
The time in each medium is inversely proportional to the speed in that medium.
The time taken in each medium will be in the inverse ratio of the time taken.
Let time in air and water be [tex]t_{1} and t_{2}[/tex].
[tex]\frac{t_{1} }{t_{2} }[/tex] = [tex]\frac{3}{16}[/tex]
Also [tex]t_{1} + t_{2}[/tex] = 12
Solving the two equations we get,
[tex]t_{1} = 1.89 seconds and t_{2} = 10.11 seconds[/tex]
