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Grade 11Mechanics

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what %age of kinetic energy of a moving particle is transferred to a stationary particle, when moving particle strikes with stationary of x times of its mass?

how can we come to know that the collision is elastic or inelastic-velocity of both bodies after collision will be same or different?

Profile image of neeru .
16 Years agoGrade 11
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Profile image of Askiitians Tutor Team
ApprovedApproved Tutor Answer1 Year ago

To determine the percentage of kinetic energy transferred from a moving particle to a stationary particle when they collide, we first need to understand the principles of momentum and kinetic energy in collisions. Let's break this down step by step.

Understanding the Collision

When a moving particle strikes a stationary particle, the outcome of the collision depends on the masses of the particles and whether the collision is elastic or inelastic. In an elastic collision, both momentum and kinetic energy are conserved, while in an inelastic collision, only momentum is conserved.

Key Concepts

  • Momentum (p): The product of mass and velocity (p = mv).
  • Kinetic Energy (KE): Given by the formula KE = 1/2 mv².
  • Elastic Collision: Both momentum and kinetic energy are conserved.
  • Inelastic Collision: Momentum is conserved, but kinetic energy is not.

Calculating Kinetic Energy Transfer

Let’s denote the mass of the moving particle as m and the mass of the stationary particle as M, where M = x * m (x is the mass ratio). If the moving particle has an initial velocity v, its initial kinetic energy (KE_initial) is:

KE_initial = 1/2 mv²

After the collision, we need to find the final velocities of both particles. In an elastic collision, the final velocities can be derived using the conservation of momentum and kinetic energy. The equations are:

  • Conservation of Momentum: mv = mv1 + Mv2
  • Conservation of Kinetic Energy: 1/2 mv² = 1/2 mv1² + 1/2 Mv2²

Final Velocities in Elastic Collision

For a perfectly elastic collision, the final velocities can be calculated as:

  • v1 (velocity of the first particle after collision): v1 = (m - M)/(m + M) * v
  • v2 (velocity of the second particle after collision): v2 = (2m)/(m + M) * v

Percentage of Kinetic Energy Transferred

To find the percentage of kinetic energy transferred to the stationary particle, we need to calculate the kinetic energy of the second particle after the collision:

KE_transferred = 1/2 Mv2²

Substituting the expression for v2, we can find the kinetic energy transferred and then calculate the percentage of the initial kinetic energy:

Percentage Transferred = (KE_transferred / KE_initial) * 100%

Determining Collision Type

To identify whether the collision is elastic or inelastic, observe the final velocities:

  • If both particles move apart with different velocities, the collision is elastic.
  • If they stick together or move with the same velocity after the collision, it is inelastic.

In summary, the percentage of kinetic energy transferred depends on the mass ratio and the nature of the collision. By applying the principles of momentum and kinetic energy conservation, you can analyze the collision and determine its characteristics effectively.