A straight piece of wire 4 cm long is placed horizontally on the surface of water annd is gently pulled up . It is found that a force of 560 dyne in addition to the weight of the wire is required for this purpose . Then surface tension of the water isA. 70 dyne/cmB. 44.8 dyne/cmC. 700 dyne/cmD. none

A straight piece of wire 4 cm long is placed horizontally on the surfa

1.	A straight piece of wire 4 cm long is placed horizontally on the surface of water annd is gently pulled up . It is found that a force of 560 dyne in addition to the weight of the wire is required for this purpose . Then surface tension of the water isA. 70 dyne/cmB. 44.8 dyne/cmC. 700 dyne/cmD. none
Answer» Correct Answer - A `T = F/(2l) = 560/(2xx4) = 70 ` dyne/cm

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