试题与答案

在弹簧限度内,弹簧挂上物体后弹簧的长度与所挂物体的质量之间的关系如下表:所挂物体

题型:解答题

题目:

在弹簧限度内,弹簧挂上物体后弹簧的长度与所挂物体的质量之间的关系如下表:
所挂物体的质量/千克012345678
弹簧的长度/cm1212.51313.51414.51515.516
(1)弹簧不挂物体时的长度是多少?
(2)如果用x表示弹性限度内物体的质量,用y表示弹簧的长度,那么随着x的变化,y的变化趋势如何?写出y与x的关系式.
(3)如果此时弹簧最大挂重量为25千克,你能预测当挂重为14千克时,弹簧的长度是多少?

答案:

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