MCQ
A force $F$ is needed to break a copper wire having radius $R$. The force needed to break a copper wire of radius $2 R$ will be
- A$F / 2$
- B$2 F$
- ✓$4 F$
- D$F / 4$
✓
Answer
Correct option: C.
$4 F$
(c) Breaking Force $\propto$ Area of cross section of wire $(\pi r)$If radius of wire is double then breaking force will become four times.
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