Question

Water rises to height of 5 cm in glass capillary tube . If the area of cross section of the tube is reduced to `((1)/(16))` th of the former value , the water rises to a height of
A. 20 cm
B. 30 cm
C. 80 cm
D. 40 cm

Answer 1

Correct Answer - A
` A_(2)=1/4A_(1)`
`pir_(2)^(2)=1/4A_(1)pir_(1)^(2)`
` r_(2) = (r_(1))/2`
`h _(2)r_(2)= h_(1)r_(1)`
`h_(2)=4xx2 = 8`