Answer:
1. 
2. 
3. 
Explanation:
Given:
- mass of slinky,

- length of slinky,

- amplitude of wave pulse,

- time taken by the wave pulse to travel down the length,

- frequency of wave pulse,

1.



2.
<em>Now, we find the linear mass density of the slinky.</em>


We have the relation involving the tension force as:




3.
We have the relation for wavelength as:



Answer:
Force on the object is 20 N
Explanation:
As we know that work done to raise the book from initial position to final position is known as potential energy stored in it
So here we know that

here we know that
U = 30 J
s = displacement = 1.5 m
so we have


Answer:
Solution is given in the attachments,below.