Two identical, thin rods, each with mass m and length L, are joined at right angles to form an L-shaped object. This object is balanced on top of a sharp edge. If the L-shaped object is deflected slightly, it oscillates.

Find the frequency of oscillation.

Respuesta :

The frequency of oscillation of the given L-shaped object made of two rods is [tex]\boxed{\frac{1}{{2\pi }}\sqrt{\frac{{3g}}{{4\sqrt2L}}}}[/tex] .

Further Explanation:

The combination of the two rods perpendicular to each other and making a L-shaped object is as shown in figure attached below.

This L-shaped object rests on a sharp edge and therefore, each rod will make an angle of [tex]45^\circ[/tex]  with the sharp edge. When there is a very small deflection in the rod, it will start performing oscillations with a small angle [tex]\theta[/tex] . Then the time period of oscillation of this rod about its center of gravity is given as:

[tex]T=2\pi \sqrt {\frac{I}{{mgd}}}[/tex]                                       …… (1)

Here, [tex]I[/tex]  is the moment of inertia of the rod, [tex]d[/tex]  is the distance of the center of gravity from the fixed point and [tex]T[/tex]  is the time period of oscillation of the L-shaped object.

The moment of inertia of the rod about its one end is given as:

[tex]I=\frac{1}{3}M{L^2}[/tex]

For the above mentioned case, the moment of inertia of the two rods about the fixed sharp point is:

[tex]\begin{aligned}I&=\frac{1}{3}m{L^2}+\frac{1}{3}m{L^2}\\&=\frac{2}{3}m{L^2}\\\end{aligned}[/tex]

The distance of the center of gravity from the fixed point is:

[tex]d=\frac{L}{{2\sqrt 2 }}[/tex]

Substitute the values in equation (1).

[tex]\begin{aligned}T&=2\pi\sqrt{\frac{{\frac{2}{3}m{L^2}}}{{mg\left({\frac{L}{{2\sqrt 2 }}}\right)}}}\\&=2\pi\sqrt{\frac{{4\sqrt 2 L}}{{3g}}}\\\end{aligned}[/tex]

The frequency of oscillation of the L-shaped object is:

[tex]\begin{aligned}f&=\frac{1}{T}\\&=\frac{1}{{2\pi}}\sqrt{\frac{{3g}}{{4\sqrt 2 L}}}\\\end{aligned}[/tex]

Thus, the frequency of oscillation of the given L-shaped object made of two rods is

[tex]\boxed{\frac{1}{{2\pi }}\sqrt{\frac{{3g}}{{4\sqrt 2 L}}}}[/tex] .

Learn More:

1. For typical rubber-on-concrete friction, what is the shortest time in which a car https://brainly.com/question/7174363

2. Protecting his nest, a 600-g peregrine falcon rams a marauding 1.5-kg raven in mid air https://brainly.com/question/6445559

3. The position of a 55 g oscillating mass is given by x(t)=(2.0cm)cos(10t) https://brainly.com/question/4544154

Answer Details:

Grade: Senior School

Subject: Physics

Chapter: Simple Harmonic Motion

Keywords:

L-shaped object, two identical thin rods, balanced, a sharp edge, deflected slightly, moment of inertia, frequency of oscillation, center of gravity.

Ver imagen snehapa

The amount of time in which an action or a state continues to exist. Due to the nature of the activity or situation under examination, it can be measured in seconds or millions of years. so, the calculted time is "[tex]\bold{2\pi \sqrt{\frac{\sqrt{2}L}{3g}}}[/tex]" .

Time period calculation:

The rod has a mass of m.

L is the length of a single rod.

If it's connecting at [tex]\bold{90^{\circ}}[/tex], as per the query,

Following that the combined system's moment of inertia.

[tex]\to \frac{mL^2}{3} + \frac{mL^2}{3}=\frac{2mL^2}{3}[/tex]

The pendulum's effective length:

[tex]\to L \cos 45^{\circ}= L \times \frac{1}{\sqrt{2}} =\frac{L}{\sqrt{2}}\\\\[/tex]

Calculating the time period:

[tex]T =2\pi \sqrt{\frac{I}{mgl}} \\\\[/tex]

   [tex]= 2\pi \sqrt{\frac{2\times mL^2 \times \sqrt{2}}{3 \times 2 mgL}}\\\\[/tex]

   [tex]= 2\pi \sqrt{\frac{L\sqrt{2}}{3 \times g}} \\\\= 2\pi \sqrt{\frac{\sqrt{2}L}{3g}}[/tex]

Find out more about the time period here:

brainly.com/question/2764183