NEET-XII-Physics

14: Some Mechanical Properties of Matter

with Solutions - page 2
Qstn# ii-3 Prvs-QstnNext-Qstn
  • #3
    A wire can sustain the weight of 20 kg before breaking. If the wire is cut into two equal parts, each part can sustain a weight of
    (a) 10 kg
    (b) 20 kg
    (c) 40 kg
    (d) 80 kg
    digAnsr:   b
    Ans : (b) 20 kg
    As the wire is cut into two equal parts, both have equal cross-sectional areas. Therefore, a weight of 20 kg exerts a force of 20g on both the pieces. Breaking stress depends upon the material of the wire. Since 20g of force is exerted on wires with equal cross-sectional areas, both the wires can sustain a weight of 20 kg.
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