Consider the following statements:
If there were no phenomenon of capillarity
- It would be difficult to use a kerosene lamp
- One would not be able to use a straw to consume a soft drink
- The blotting paper would paper would fail to function
- The big trees that we see around would not have grown on the earth
Which of the following statements given above are correct?
[UPSC Civil Services Exam – 2012 Prelims]
(a) 1, 2 and 3 only
(b) 1, 3 and 4 only
(c) 2 and 4 only
(d) 1, 2, 3 and 4
Answer: (b)
Explanation:
Capillarity – The tendency of a liquid in a capillary tube or absorbent material to rise or fall as a result of surface tension.
- The threads in the wick of a lamp cause the oil to rise due to capillary action. This statement is true.
- Using a straw to drink a soft drink does not involve capillary action because additional pressure from the mouth is applied. Therefore, this statement is false.
- Blotting paper absorbs ink through the capillary action of its pores. This statement is true.
- Plants draw water from the soil through capillary action in the root-hairs. This statement is true.