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David G asked in Science & MathematicsPhysics · 1 decade ago

Relativistic velocity of a body under constant acceleration?

Relativistic momentum, p = γ m_0 v, where γ is Lorentz factor 1/√(1 - v²/c²) and m_0 is rest mass of the body in question

Newton's 2nd, which still holds, is F= dp/dt

Assuming body starts at rest, change in momentum is still impulse thus if a force F acts on mass m_0 for t then γ m_0 v = F t

All correct so far?

Thus, for velocity as function of time (in the unaccelerated reference frame) I get

v(t) = (c F t)/√(m_0² c² + F² t²)

Is this correct?

1 Answer

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  • 1 decade ago
    Favorite Answer

    Is Not correct.

    The equation ( γ *mo v = Ft) is also not correct.

    This is correct only for a small interval of time.

    Hence you have to wirte this as

    γ *mo v = F dt.

    ===========================

    The correct form is Fdt = d(mv) where m and v are variables and m depnends on v.

    d(mv) = mdv/dt + v dm/dt

    =================================

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