Explore BrainMass

Explore BrainMass

    Initial velocities of two particles

    This content was COPIED from BrainMass.com - View the original, and get the already-completed solution here!

    Two particles, of mass 1 kg and 3 kg, are traveling towards each other with velocities of 100 m/s and -40 m/s respectively. Using the laws of physics (e.g. conservation of energy & momentum) calculate the following:
    a) What are the initial energies of the particles?
    b) What are the final velocities of the particles?
    c) Which particle gained energy, and which lost energy?

    © BrainMass Inc. brainmass.com February 24, 2021, 2:08 pm ad1c9bdddf
    https://brainmass.com/physics/energy/initial-velocities-two-particles-3522

    Solution Preview

    Please see attached.

    Two particles, of mass 1 kg and 3 kg, are traveling towards each other with velocities of 100 m/s and -40 m/s respectively. Using the laws of physics (e.g. conservation of energy & momentum) calculate the following:
    a) What are the initial energies of the particles?
    b) What are the final velocities of the particles?
    c) Which particle gained energy, and which lost energy?

    a) The initial energies are given by the equation:
    Ei = 0.5*m*v2

    For particle 1:
    Ei = 0.5*m¬1*v12
    = 0.5*(1 kg)*(100 m/s)2
    = (0.5 kg)*(10,000 m2/s2)
    = 5000 kg*m2/s2

    The unit [kg*m2/s2] is not a familiar unit of energy, so we should check to see if it is correct:
    kg*m2/s2 = m*(kg*m/s2) = m*N = J

    So we see that [kg*m2/s2] = [J], (joule) which is the SI unit of energy.

    For particle 2:
    Ei = 0.5*m2*v22
    = 0.5*(3 kg)*(-40 m/s)2
    = (1.5 kg)*(1600 m2/s2)
    = 2400 J

    b) The conservation of momentum & energy say that
    Pi = Pf
    (the initial momentum equals the final momentum)

    Ei = Ef
    (the initial energy equals the final ...

    Solution Summary

    The initial velocities of two particles are given. The particles of gained energy are determined.

    $2.19

    ADVERTISEMENT