Minimum speed at top of vertical circle (v_min = √(rg) at top of circle)

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v_min = √(rg) at top of circle

What each symbol means

SymbolWhat it stands for
gAcceleration due to gravity (9.8 m/s²)
rRadius of the vertical circle (m)
v_minMinimum speed at the top (m/s)

When to use this

For string/rod: at top, tension ≥ 0 gives v ≥ √(rg). At bottom: v ≥ √(5rg) for complete circle. For rigid rod: v_min = 0 at top (rod can push). Energy conservation: ½mv²_bottom = ½mv²_top + 2mgr.