Solving SHM Kinematics: Find the Period!

In summary, the conversation involves a person struggling with solving SHM kinematics problems and looking for help. They post a specific problem involving a 1 kg block oscillating on a spring. They provide some equations and variables they have already figured out, but are still looking for hints and help with solving the problem. Eventually, they realize they had forgotten what they were solving for and are able to solve the problem on their own.
  • #1
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Hi there I'm having a little trouble doing problems with SHM kinematics. I think its because I have yet to find a good method of solving them. I'll post one and show what I can do. Them I hope somone can help me find a good method to solving it.A 1 kg block oscillates on a spring with k= 20 N/m. At t= 0s the block is 20cm to the right of equilibrium. and moving to the left with v= -100cm/s.
What is the Period?All I can figure out is that [tex] \phi_0 = \cos^{-1} (\frac{x_0}{A}) [/tex]

And that [tex] T= 2\pi \sqrt{\frac{m}{k}} = 1.40s [/tex]

Any hints at all? I can't seem to find any expression for the other variables that'll help, but maybe I'm forgetting some. Any help?
 
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  • #2
WAIIIIIIIIIT A MINUTE I SOLVED THIS I forgot what i was solveing for sry!
 
  • #3


Hello there,

I understand that you are having trouble with solving SHM kinematics problems and are looking for some guidance. SHM or Simple Harmonic Motion is a fundamental concept in physics and it involves oscillatory motion of a system around an equilibrium point. In your problem, a 1 kg block is oscillating on a spring with a spring constant of 20 N/m.

To find the period of the oscillation, we can use the formula T=2π√(m/k), where m is the mass of the block and k is the spring constant. As you have correctly calculated, the period is 1.40 seconds. However, this formula only works for simple harmonic motion with no initial velocity.

In your problem, the block has an initial velocity of -100 cm/s and is 20 cm to the right of equilibrium at t=0s. To solve this problem, we need to use the equation x(t)=Acos(ωt+φ), where A is the amplitude, ω is the angular frequency and φ is the phase angle. We can find these values by using the initial conditions provided in the problem.

First, we can find the amplitude A by using the formula A=√(x0^2+v0^2/ω^2), where x0 is the initial displacement and v0 is the initial velocity. In this case, A=√(20^2+(-100)^2/ω^2)=√(400+10000/ω^2)=√(10400/ω^2).

Next, we can find the angular frequency ω by using the formula ω=√(k/m), where k is the spring constant and m is the mass of the block. In this case, ω=√(20/1)=√20.

Finally, we can find the phase angle φ by using the formula φ=cos^-1(x0/A), where x0 is the initial displacement and A is the amplitude. In this case, φ=cos^-1(20/√(10400/ω^2)).

Now, we can plug in these values in the equation x(t)=Acos(ωt+φ) to get the equation of motion for the block. From this equation, we can find the period by calculating the time it takes for the block to complete one full oscillation, which is the period.

I hope
 

FAQ: Solving SHM Kinematics: Find the Period!

What is SHM kinematics?

SHM (Simple Harmonic Motion) kinematics is a type of motion where an object oscillates back and forth in a regular pattern, such as a pendulum or a spring. It follows the laws of harmonic motion, where the restoring force is directly proportional to the displacement from equilibrium.

How do you find the period of SHM kinematics?

The period of SHM kinematics is the time it takes for one complete cycle of motion. To find the period, you can use the formula T = 2π√(m/K), where T is the period, m is the mass of the object, and K is the spring constant. This formula can also be used for other types of SHM kinematics, such as a simple pendulum.

What is the relationship between period and frequency in SHM kinematics?

The period and frequency of SHM kinematics are inversely proportional to each other. This means that as the period increases, the frequency decreases and vice versa. The formula for frequency is f = 1/T, where T is the period. In other words, the frequency is the number of cycles per unit time.

How does amplitude affect the period of SHM kinematics?

The amplitude of SHM kinematics refers to the maximum displacement from equilibrium. It does not have a direct effect on the period, but it does affect the speed of the object. A larger amplitude results in a higher speed, which can impact the period if there is friction or air resistance present.

Can SHM kinematics be applied to real-world situations?

Yes, SHM kinematics can be applied to real-world situations. Many objects and phenomena in nature exhibit SHM, such as the motion of a swing, the vibration of a guitar string, and the motion of a mass-spring system. By understanding the principles of SHM kinematics, we can better understand and predict the behavior of these systems.

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