The second, fourth, and seventh answers apply. Energy in a closed system is conserved, but it can change form
Answer:78 N
Explanation:Impulse=Force*time
=39*2 =78 Ns
Answer:
"Longitudinal wave" is the appropriate answer.
Explanation:
- Generating waves whenever the form of communication being displaced in a similar direction as well as in the reverse way of the wave's designated points, could be determined as Longitudinal waves.
- A wave running the length of something like a Slinky stuffed animal, which expands as well as reduces the spacing across spindles, produces a fine image or graphic.
The initial kinetic energy of the boat and its rider is

After Sam stops it, the final kinetic energy of the boat+rider is

because its final velocity is zero.
For the law of conservation of energy, the work done by Sam is the variation of kinetic energy of the system:

where the negative sign is due to the fact that the force Sam is applying goes against the direction of motion of the boat.