Answer:

Explanation:
According to the law of conservation of linear momentum, the total momentum of both pucks won't be changed regardless of their interaction if no external forces are acting on the system.
Being
and
the masses of pucks a and b respectively, the initial momentum of the system is

Since b is initially at rest

After the collision and being
and
the respective velocities, the total momentum is

Both momentums are equal, thus
Solving for 


The initial kinetic energy can be found as (provided puck b is at rest)


The final kinetic energy is


The change of kinetic energy is

Answer:
2.78 m
Explanation:
At the peak, the velocity is 0.
Given:
a = -1.6 m/s²
v₀ = 2.98 m/s
v = 0 m/s
x₀ = 0 m
Find:
x
v² = v₀² + 2a(x - x₀)
(0 m/s)² = (2.98 m/s)² + 2(-1.6 m/s²) (x - 0 m)
x = 2.775 m
Rounded to 3 sig-figs, the astronaut halloweener reaches a maximum height of 2.78 meters.
Answer:
Action - Pulling up the train.
Reaction - Friction on the locomotive
Explanation:
Locomotive is pulling the train upwards ,
Which is the action force applied by the locomotive,
As a reaction locomotive will be pulled by the train which is the reaction of pulling
Now, considering it as a action on locomotive , friction force will act on it as a reaction upwards which will result to move it upwards.
For train action is pulling up by locomotive and reaction will be friction acting on it downwards.
i sorry i thought of geocentric as something else it appears that the earth was the center