Answer:
The value is 
Explanation:
From the question we are told that
The mass of the object is 
The unstressed length of the string is 
The length of the spring when it is at equilibrium is 
The initial speed (maximum speed)of the spring when given a downward blow 
Generally the maximum speed of the spring is mathematically represented as

Here A is maximum height above the floor (i.e the maximum amplitude)
and
is the angular frequency which is mathematically represented as

So

=> 
Gnerally the length of the compression(Here an assumption that the spring was compressed to the ground by the hammer is made) by the hammer is mathematically represented as

=> 
=> 
Generally at equilibrium position the net force acting on the spring is

=> 
=> 
So

=> 
I think the answer is c but I’m not sure
Answer:
<em>The coefficient of static friction between the crate and the floor is 0.41</em>
Explanation:
<u>Friction Force</u>
When an object is moving and encounters friction in the air or rough surfaces, it loses acceleration and velocity because the friction force opposes motion.
The friction force when an object is moving on a horizontal surface is calculated by:
[1]
Where
is the coefficient of static or kinetics friction and N is the normal force.
If no forces other then the weight and the normal are acting upon the y-direction, then the weight and the normal are equal in magnitude:
N = W = m.g
The crate of m=20 Kg has a weight of:
W = 20*9.8
W = 196 N
The normal force is also N=196 N
We can find the coefficient of static friction by solving [1] for
:

The friction force is equal to the minimum force required to start moving the object on the floor, thus Fr=80 N and:


The coefficient of static friction between the crate and the floor is 0.41
Yes thank u teehee
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