Answer:
Part a)

Part b)
Here final kinetic energy is more than the initial kinetic energy
This increase in kinetic energy is due to spring connected between them as the spring energy is converted into kinetic energy of two blocks
Explanation:
Part a)
As we know that there is no external force on the system of two gliders
So here we can use momentum conservation for two gliders
So we will have




Part b)
now we will have
initial kinetic energy of both gliders is given as


Final kinetic energy of two gliders


so here final kinetic energy is more than the initial kinetic energy
This increase in kinetic energy is due to spring connected between them as the spring energy is converted into kinetic energy of two blocks
Answer:
.
Explanation:
The average speed of an object is equal to total distance over total time.
- Distance traveled:
.
How much time is taken? This trip is divided into two halves, each of distance
.
Time spent on the first half of the trip:
.
Similarly, time spent on the second half of the trip:
.
In total:
.
Average speed:
.
This value turned out to be slightly different from the average of the speed during the two halves of the journey. The reason is that the object traveled at each speed for a different amount of time. It spent more time at the slower speed, which gives that speed a greater weight in the average. That explains why the average speed is closer to
rather than
.