A rectangular film of liquid is extended from | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(D) The work done in stretching a liquid film is given by $W = T 	imes \Delta A_{total}$.Since a liquid film has two surfaces,the change in area is $

Vedclass · Accepted Answer

$0.125$

Vedclass · Answer

(D) The work done in stretching a liquid film is given by $W = T 	imes \Delta A_{total}$.Since a liquid film has two surfaces,the change in area is $\Delta A_{total} = 2 	imes (A_2 - A_1)$.Initial area $A_1 = 4 \, cm 	imes 2 \, cm = 8 \, cm^2 = 8 	imes 10^{-4} \, m^2$.Final area $A_2 = 5 \, cm 	imes 4 \, cm = 20 \, cm^2 = 20 	imes 10^{-4} \, m^2$.Change in area $\Delta A = A_2 - A_1 = 12 \, cm^2 = 12 	imes 10^{-4} \, m^2$.Total change in area $\Delta A_{total} = 2 	imes 12 	imes 10^{-4} \, m^2 = 24 	imes 10^{-4} \, m^2$.Given work done $W = 3 	imes 10^{-4} \, J$.Using $W = T 	imes \Delta A_{total}$,we get $T = \frac{W}{\Delta A_{total}} = \frac{3 	imes 10^{-4}}{24 	imes 10^{-4}} = \frac{1}{8} = 0.125 \, N \, m^{-1}$.

$A$ rectangular film of liquid is extended from $(4 \, cm \times 2 \, cm)$ to $(5 \, cm \times 4 \, cm).$ If the work done is $3 \times 10^{-4} \, J,$ the value of the surface tension of the liquid is ............ $N \, m^{-1}$

Similar Questions

$A$ rectangular film of liquid is expanded from $(5 \text{ cm} \times 4 \text{ cm})$ to $(7 \text{ cm} \times 8 \text{ cm})$. If the work done is $3 \times 10^{-4} \text{ J}$,the surface tension of the liquid is (nearly):

$A$ metal wire of length $L$ and density $d$ floats horizontally on the free surface of water. What is the maximum radius of the wire such that it does not sink in water? [$T$ = surface tension of water, $g$ = gravitational acceleration]

Two pieces of glass plates placed one upon the other with a little water in between them cannot be separated easily because of:

If temperature increases,the surface tension of a liquid

Why are small drops of liquid spherical in shape?

Vedclass Test Series

Exam Paper Generator

Online Exam Module