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