Respuesta :
A) 4.58 cm
B) 8.97 J
Explanation:
A)
When the child is balanced on the spring, the weight of the child (downward force) is balanced by the restoring force of the spring (upward force). Therefore, we can write:
[tex]W=F\\mg=kx[/tex]
where:
m = 40 kg is the mass of the child
[tex]g=9.8 m/s^2[/tex] is the acceleration due to gravity
k = 8,550 N/m is the spring constant
x is the compression of the spring, with respect to the equilibrium position
Solving for x, we find:
[tex]x=\frac{mg}{k}=\frac{(40)(9.8)}{8550}=0.0458 m = 4.58 cm[/tex]
So, the spring is compressd by 4.58 cm.
B)
The elastic potential energy stored in a compressed spring is given by
[tex]E=\frac{1}{2}kx^2[/tex]
where
k is the spring constant
x is the compression of the spring
In this problem, we have:
k = 8550 N/m (spring constant)
x = 0.0458 m (compression)
So, the elastic energy stored is:
[tex]E=\frac{1}{2}(8550)(0.0458)^2=8.97 J[/tex]
Hooks Law states that the force needed to compress the spring is directly proportional to the distance. Ā The spring compressed by the child is 4.58 cm and the energy in the spring is 8.97 J.
Hooks Law of spring:
It states that the force needed to compress or stretch the spring is directly proportional to the distance.
[tex]\bold {F = K\times X}[/tex]
Where
F - force = [tex]\bold {m\times g}[/tex] = [tex]40\times 9.8[/tex] = 392 N
K - spring constant = Ā 8,550 N/m.
X - distance = ?
So, [tex]\bold{X = \frac{F}{K}}[/tex]
Now put the values,
[tex]\bold {X= \frac{392N }{8550N/m} }\\\\\bold {X= 4.58 cm }\\[/tex]
Formula for potential energy in the compressed spring,
[tex]\bold{E = \frac{1}{2}K x^2 }[/tex]
Put the values in the formula,
[tex]\bold{E = \frac{1}{2}8550 \times 4.58^2 }\\\\\bold{E = 8.97 J}[/tex]
Therefore, the spring compressed by child is 4.58 cm and the energy in the spring is 8.97 J.
To know more about energy of compressed spring, refer to the link:
https://brainly.com/question/12644717