Properties Of Solids And Liquids Question 372
Question: Force necessary to pull a circular plate of 5 cm radius from water surface for which surface tension is 75 dynes/cm, is [MP PMT 1991]
Options:
A) $ 30dyne $
B)60 dynes
C) 750 dynes
D)750 $ \pi $ dynes
Show Answer
Answer:
Correct Answer: D
Solution:
The total length of the circular plate on which the force will act $ =2\pi R $
Force to pull$ =2\pi RT=2\times \pi \times 5\times 75=750\pi $ dynes
