Question

19. Two glass plates are separated by water. If surface
tension of water is 75 dyne per cm and area of each
plate wetted by water is 8 cm² and the distance
between the plates is 0.12 mm, then the force
applied to separate the two plates is:
(a) 102 dyne (b) 104 dyne
(c) 10dyne (d) 10° dyne​

Answer 1

Answer:

Explanation:

⇒A=8 cm²,

⇒t=0.12 mm,

⇒F applied=F t,

F t=σ×l,

⇒75×A/t,

⇒75×8/0.012,

⇒total F t=2×75×8×10/0.12,

⇒ 10 to the power 5 dyne is the answer.