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The potential energy (U) of a body of u...

The potential energy (U) of a body of unit mass moving in a one-dimension foroce field is given by
`U=(x^(2)-4x+3)` . All untis are in S.L

A

a. Find the equilibrium position of the body

B

b. Show that oscilliations of the body about this equilibrium positon in sample harmonic motion and find its time period

C

c. Find the amplitude of oscilliations if speed of the body at equilibrium position is `2sqrt6 m//s`

D

d. Find the amplitude of oscillators if speed of the body at equilibrium position is `2sqrt(6) m//s`.

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To solve the problem step by step, we will break down the question into parts and provide a clear explanation for each step. ### Given: The potential energy \( U \) of a unit mass body in a one-dimensional force field is given by: \[ U = x^2 - 4x + 3 \] ### Step 1: Find the Equilibrium Position The equilibrium position occurs where the net force acting on the body is zero. The force \( F \) can be derived from the potential energy using the relation: \[ F = -\frac{dU}{dx} \] First, we need to differentiate \( U \): 1. Differentiate \( U \): \[ U = x^2 - 4x + 3 \] \[ \frac{dU}{dx} = 2x - 4 \] 2. Set the force to zero: \[ F = -\frac{dU}{dx} = 0 \implies - (2x - 4) = 0 \] \[ 2x - 4 = 0 \implies 2x = 4 \implies x = 2 \] **Equilibrium Position**: \( x = 2 \) ### Step 2: Show that the Oscillation is Simple Harmonic Motion (SHM) To show that the oscillation is SHM, we need to express the force in the form: \[ F = -k(x - x_0) \] where \( k \) is a positive constant and \( x_0 \) is the equilibrium position. From our earlier calculation: \[ F = -\frac{dU}{dx} = - (2x - 4) = -2(x - 2) \] This shows that: \[ F = -2(x - 2) \] Here, \( k = 2 \) and \( x_0 = 2 \). This confirms that the motion is SHM since the force is proportional to the displacement from the equilibrium position. ### Step 3: Calculate the Time Period The time period \( T \) of SHM can be calculated using the formula: \[ T = 2\pi \sqrt{\frac{m}{k}} \] Given that the mass \( m = 1 \) (unit mass) and \( k = 2 \): \[ T = 2\pi \sqrt{\frac{1}{2}} = 2\pi \cdot \frac{1}{\sqrt{2}} = \sqrt{2} \cdot 2\pi \] **Time Period**: \( T = \sqrt{2} \cdot 2\pi \) ### Step 4: Calculate the Amplitude of Oscillation Given the speed at equilibrium \( v = 2\sqrt{6} \) m/s, we know that at the equilibrium position, the speed is the maximum speed \( v_{\text{max}} \): \[ v_{\text{max}} = A \omega \] where \( A \) is the amplitude and \( \omega \) is the angular frequency. From the previous calculations, we know: \[ \omega = \sqrt{k/m} = \sqrt{2} \] Now, substituting the values: \[ 2\sqrt{6} = A \cdot \sqrt{2} \] Solving for \( A \): \[ A = \frac{2\sqrt{6}}{\sqrt{2}} = 2\sqrt{3} \] **Amplitude**: \( A = 2\sqrt{3} \) ### Summary of Results: 1. **Equilibrium Position**: \( x = 2 \) 2. **Oscillation Type**: Simple Harmonic Motion (SHM) 3. **Time Period**: \( T = \sqrt{2} \cdot 2\pi \) 4. **Amplitude**: \( A = 2\sqrt{3} \)
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