Q.

A needle of length 5cm is floating on water of surface tension 0.07 Jm-2 and is not wetted by water.  Then the weight of the needle will be

see full answer

Start JEE / NEET / Foundation preparation at rupees 99/day !!

21% of IItians & 23% of AIIMS delhi doctors are from Sri Chaitanya institute !!
An Intiative by Sri Chaitanya

a

7 x 10-3 N  

b

0.7 x 10-3 N                           

c

5.2 x 10-2 N                                     

d

2 x 10-2 N

answer is A.

(Unlock A.I Detailed Solution for FREE)

Ready to Test Your Skills?

Check your Performance Today with our Free Mock Test used by Toppers!

Take Free Test

Detailed Solution

detailed_solution_thumbnail

Weight of the neddle is balanced by surface tensional force

T x 2l = mg

0.07 x 2 x 5 x 10-2 = mg

mg = 7 x 10-3 N

Watch 3-min video & get full concept clarity

hear from our champions

score_test_img

Get Expert Academic Guidance – Connect with a Counselor Today!

whats app icon
A needle of length 5cm is floating on water of surface tension 0.07 Jm-2 and is not wetted by water.  Then the weight of the needle will be