将一根长为\(L\)的光滑细钢丝\(ABCDE\)制成如图所示的形状,并固定在竖直平面内\(.\)其中\(AD\)段竖直,\(DE\)段为\( \dfrac{3}{4} \)圆弧,圆心为\(O\),\(E\)为圆弧最高点,\(C\)与\(E\)、\(D\)与\(O\)分别等高,\(BC= \dfrac{1}{4} AC.\)将质量为\(m\)的小珠套在钢丝上由静止释放,不计空气阻力,重力加速度为\(g\).
\((1)\)小珠由\(C\)点释放,求到达\(E\)点的速度大小\(v_{1}\);
\((2)\)小珠由\(B\)点释放,从\(E\)点滑出后恰好撞到\(D\)点,求圆弧的半径\(R\);
\((3)\)欲使小珠到达\(E\)点与钢丝间的弹力超过\( \dfrac{mg}{4} \),求释放小珠的位置范围.