An ocean fishing boat is drifting just above a school of tuna on a foggy day. Without warning, an engine backfire occurs on another boat 1.0 km away. How much time elapses before the backfire is heard by the fish (a)

0.641 seconds

Explanation:

Distance (d) = 1.0 km

Using the relation :

Speed = distance / time

Time = distance / speed

Speed of sound in seawater is about 1560 m/s

Distance = 1.0km =

1km = 1000m

Time = 1000 / 1560

Time = 0.6410256

Time = 0.641 s

the answer would be c

note: the given question is incomplete.

complete question is given below.

which is an example of kinetic energy?

a. the energy stored in ethanol  

b. a hockey puck sliding across the ice  

c. a compressed spring  

d. a ball sitting at the top of a ramp

solution: the kinetic energy is the energy posses by the virtue of the motion of the object.

in the given options, a, c and d are the example of potential energy because it is the energy posses by the virtue of the rest of the object. but option b has the kinetic energy as the object is in motion.

hence, a hockey puck sliding across the ice   is the apex example of kinetic energy.

so, the option (b) a hockey puck sliding across the ice   is the correct option.