The speed of sound waves through ocean water is 1437 m/s. Assume that ultrasound waves take 2 seconds to travel from
a sonar device on a ship to the bottom of the water and back
to the ship again. How deep is the water?

    5.5 n======    assuming that      we have      m = 0.145 kg    a = 38 m/s²therefore    5.51 n, but two significant figures.final answer: 5.5 n

I'm having some difficulty seeing the diagram clearly.but the question says there's a net inward force on the object.so we know right away,  from newton's 2nd law of motion, thatthat baby is accelerating.  it doesn't even matter which way thenet force is pointing.  if there's any net force, then either theobject's speed or else its direction must be changing.

Electricity and discharge