CameraIcon
CameraIcon
SearchIcon
MyQuestionIcon


Question

Two wires are made of the same material and have the same volume. The first wire has cross-sectional area A and the second wire has cross-sectional area $$3$$A. If the length of the first wire is increased by $$\Delta$$l on applying a force F, how much force is needed to stretch the second wire by the same amount?


A
4F
loader
B
9F
loader
C
F
loader
D
6F
loader

Solution

The correct option is D $$9$$F

L, v, same

From Hooke’s law

$$\displaystyle\frac{F}{A}=4\frac{\Delta l}{L}$$                          $$v_1=v_2$$

$$F=y\frac{A\Delta l}{L}$$                      $$A\times l=3A\times l_1$$ $$\Rightarrow l_1=l_{/3}$$

$$\Rightarrow \displaystyle\frac{F}{F_1}=\frac{\displaystyle\frac{A\Delta l}{l}}{\displaystyle\frac{3A\Delta l}{l_{/3}}}$$ $$\Rightarrow F_1=9F$$

Option (2).


Physics

Suggest Corrections
thumbs-up
 
0


similar_icon
Similar questions
View More


similar_icon
People also searched for
View More



footer-image