Answer is: 1973.17N aprox.
step by step in the pic below
To solve this exercise, it is necessary to apply the concepts of conservation of the moment especially in objects that experience an inelastic colposition.
They are expressed as,

Where,
= mass of the skier
= mass of the cat
= initial velocity of skier
= initial velocity of cat
= final velocity of both
Re-arrange to find V_f we have,



Once the final velocity is found it is possible to calculate the change in kinetic energy, so




Therefore the amount of kinetic energy converted in to internal energy is 819J
Answer: The period of a spring if it has a mass of 5 kg and a spring constant of 6 N/m is 5.73 sec.
Explanation:
Given: Mass = 5 kg
Spring constant = 6 N/m
Formula used to calculate period is as follows.

where,
T = period
m = mass
k = spring constant
Substitute the values into above formula as follows.

Thus, we can conclude that the period of a spring if it has a mass of 5 kg and a spring constant of 6 N/m is 5.73 sec.
Answer: true
(I need 20 characters to submit the answer so I wrote this not to be confused with the answer)