Protons, electrons, neutrons, and particles have the same momentum. Which of them has the highest K.E?
Correct answer: B. Electron
- A. Proton
- B. Electron
- C. Neutron
- D. alpha-particle
Explanation
The momentum of a particle is given by the product of its mass and velocity. Since both protons and electrons have the same momentum, it means they must have different velocities due to their different masses.The kinetic energy (K.E) of a particle is given by the equation K.E = (1/2) mv^2, where m is the mass of the particle and v is its velocity.Comparing protons, electrons, and neutrons:Protons have a relatively larger mass compared to electrons and neutrons.Neutrons have a slightly larger mass than protons.Electrons have a much smaller mass compared to protons and neutrons.Given that momentum is the same for all three particles, and momentum is given by the product of mass and velocity, we can conclude that the velocities of protons, electrons, and neutrons must be different.Since kinetic energy depends on the mass and the square of the velocity, the particle with the highest kinetic energy will be the one with the highest velocity.Therefore, the electron, which has the smallest mass among the three particles, will have the highest kinetic energy. The higher velocity of the electron compensates for its smaller mass, resulting in a greater kinetic energy compared to protons and neutrons.
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About Work and Energy
Work transfers energy when a force causes displacement, while kinetic energy, gravitational potential energy and power describe motion, position and the rate of energy transfer. The work-energy theorem links net work with change in kinetic energy, and efficiency accounts for energy losses rather than treating them as energy destruction.
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