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A particle of mass m, kinetic energy K a...

A particle of mass `m`, kinetic energy `K` and momentum `p` collides head on elastically with another particle of mass `2 m` at rest. After collision, :
`{:(,"Column I",,"Column II",),((A),"Momentum of first particle",(p),3//4 p,),((B),"Momentum of second particle",(q),-K//9,),((C ),"Kinetic energy of first particle",(r ),-p//3,),((D),"Kinetic energy of second particle",(s),(8K)/(9),),(,,(t),"None",):}`

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To solve the problem, we will analyze the elastic collision between two particles: one with mass `m`, kinetic energy `K`, and momentum `p`, and another with mass `2m` at rest. We will use the principles of conservation of momentum and conservation of kinetic energy. ### Step 1: Conservation of Momentum The initial momentum of the system is given by the momentum of the first particle since the second particle is at rest: \[ p_{\text{initial}} = mv + 0 = mv \] After the collision, let the velocities of the first and second particles be \(v_1\) and \(v_2\) respectively. The final momentum is: \[ p_{\text{final}} = mv_1 + 2mv_2 \] By conservation of momentum: \[ mv = mv_1 + 2mv_2 \] Dividing through by \(m\): \[ v = v_1 + 2v_2 \quad \text{(1)} \] ### Step 2: Conservation of Kinetic Energy For an elastic collision, the total kinetic energy before and after the collision is conserved. The initial kinetic energy is: \[ K_{\text{initial}} = \frac{1}{2}mv^2 \] The final kinetic energy is: \[ K_{\text{final}} = \frac{1}{2}mv_1^2 + \frac{1}{2}(2m)v_2^2 = \frac{1}{2}mv_1^2 + mv_2^2 \] By conservation of kinetic energy: \[ \frac{1}{2}mv^2 = \frac{1}{2}mv_1^2 + mv_2^2 \] Dividing through by \(m\): \[ \frac{1}{2}v^2 = \frac{1}{2}v_1^2 + v_2^2 \quad \text{(2)} \] ### Step 3: Solve the Equations From equation (1), we can express \(v_1\) in terms of \(v_2\): \[ v_1 = v - 2v_2 \] Substituting this into equation (2): \[ \frac{1}{2}v^2 = \frac{1}{2}(v - 2v_2)^2 + v_2^2 \] Expanding the square: \[ \frac{1}{2}v^2 = \frac{1}{2}(v^2 - 4vv_2 + 4v_2^2) + v_2^2 \] Combining terms: \[ \frac{1}{2}v^2 = \frac{1}{2}v^2 - 2vv_2 + 2v_2^2 \] Cancelling \(\frac{1}{2}v^2\) from both sides: \[ 0 = -2vv_2 + 2v_2^2 \] Factoring out \(2v_2\): \[ 0 = 2v_2(v_2 - v) \] This gives us two solutions: 1. \(v_2 = 0\) (not possible since the second particle is at rest) 2. \(v_2 = v\) ### Step 4: Find Velocities Substituting \(v_2 = v\) back into equation (1): \[ v = v_1 + 2v \implies v_1 = v - 2v = -v \] ### Step 5: Calculate Momentum and Kinetic Energy Now we can find the momentum and kinetic energy for both particles after the collision: - **Momentum of first particle**: \[ p_1 = mv_1 = m(-v) = -mv = -p \] - **Momentum of second particle**: \[ p_2 = 2mv_2 = 2m(v) = 2mv = 2p \] - **Kinetic energy of first particle**: \[ K_1 = \frac{1}{2}m(v_1^2) = \frac{1}{2}m(v^2) = \frac{1}{2}mv^2 = K \] - **Kinetic energy of second particle**: \[ K_2 = \frac{1}{2}(2m)(v_2^2) = mv^2 = 2K \] ### Final Results - Momentum of first particle: \( -p \) - Momentum of second particle: \( 2p \) - Kinetic energy of first particle: \( K \) - Kinetic energy of second particle: \( 2K \) ### Matching with Options - **(A)** Momentum of first particle: \( -p \) (not in options) - **(B)** Momentum of second particle: \( 2p \) (not in options) - **(C)** Kinetic energy of first particle: \( K \) (not in options) - **(D)** Kinetic energy of second particle: \( 2K \) (not in options)

To solve the problem, we will analyze the elastic collision between two particles: one with mass `m`, kinetic energy `K`, and momentum `p`, and another with mass `2m` at rest. We will use the principles of conservation of momentum and conservation of kinetic energy. ### Step 1: Conservation of Momentum The initial momentum of the system is given by the momentum of the first particle since the second particle is at rest: \[ p_{\text{initial}} = mv + 0 = mv \] After the collision, let the velocities of the first and second particles be \(v_1\) and \(v_2\) respectively. The final momentum is: \[ p_{\text{final}} = mv_1 + 2mv_2 \] By conservation of momentum: ...
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