contestada

A 4.00-kg object is attached to a spring and placed on frictionless, horizontal surface. A horizontal force of 27.0 N is required to hold the object at rest when it is pulled 0.200 m from its equilibrium position (the origin of the x axis). The object is now released from rest from this stretched position, and it subsequently undergoes simple harmonic oscillations.
(a) Find the force constant of the spring.
N/m
(b) Find the frequency of the oscillations.
Hz
(c) Find the maximum speed of the object.
m/s
(d) Where does this maximum speed occur?
x = ± m
(e) Find the maximum acceleration of the object.
m/s2
(f) Where does the maximum acceleration occur?
x = ± m
(g) Find the total energy of the oscillating system.
J
(h) Find the speed of the object when its position is equal to one-third of the maximum value.
m/s
(i) Find the magnitude of the acceleration of the object when its position is equal to one-third of the maximum value.
m/s^2

Respuesta :

Answer:

a)

[tex]135[/tex]Nm⁻¹

b)

[tex]0.925[/tex] Hz

c)

[tex]1.2[/tex]ms⁻¹

d)

[tex]0[/tex] m

e)

[tex]6.7[/tex]ms⁻²

f)

[tex]\pm 0.2[/tex] m

Explanation:

a)

[tex]F[/tex] = force required to hold the object at rest connected with stretched spring = 27 N

[tex]x[/tex] = stretch in the spring from equilibrium position = 0.2 m

[tex]k[/tex] = force constant of the spring

force required to hold the object at rest is same as the spring force , hence

[tex]F = k x[/tex]

[tex]k = \frac{F}{x}[/tex]

inserting the values

[tex]k = \frac{27}{0.2} = 135[/tex] Nm⁻¹

b)

frequency of the oscillations is given as

[tex]f =\frac{1}{2\pi }\sqrt{\frac{k}{m}}[/tex]

inserting the values

[tex]f =\frac{1}{2(3.14) }\sqrt{\frac{135}{4}}\\f = 0.925[/tex] Hz

c)

[tex]A[/tex] = Amplitude of oscillations = 0.2 m

[tex]w[/tex] = angular frequency

Angular frequency is given as

[tex]w = 2\pi f = 2 (3.14) (0.925) = 5.8[/tex] rads⁻¹

Maximum speed of oscillation is given as

[tex]v_{max} = Aw[/tex]

[tex]v_{max} = (0.2)(5.8)\\v_{max} = 1.2[/tex] ms⁻¹

d)

maximum speed of the object occurs at the equilibrium position, hence

[tex]x = 0[/tex] m

e)

Maximum acceleration of oscillation is given as

[tex]a_{max} = Aw^{2}[/tex]

[tex]a_{max} = (0.2)(5.8)^{2}\\a_{max} = 6.7[/tex]ms⁻²

f)

maximum acceleration occurs when the object is at extreme positions, hence

[tex]x = \pm 0.2[/tex] m