this was a question in class 10 maths paper for st georges school-alaknanda
Q. A 15 cm long test tube having diameter of 3.6 cm has water
upto a height of 6 cm. 20 spherical drops of oil of radius 9 mm are dropped
into it. What length of test tube
remains empty?.............tell me the solution to this problem or where the solution exists....
hardikpandey:
someone with brains can do it....
Answers
Answered by
35
diameter of the tube=3.6cm
⇒radius=1.8cm=18mm
total height=15cm=150mm
let height upto water=L=6cm=60mm
volume of 20 oil drops=20×(4/3)πr³
=20×4×9×9×9×22÷(7×3)
=80×729×22÷21
=61097.14286mm³
=61.09714286cm³
πr²h=61·9714286cm³
⇒h=6cm
⇒remaining height=15-(6+6)cm
=3cm
⇒radius=1.8cm=18mm
total height=15cm=150mm
let height upto water=L=6cm=60mm
volume of 20 oil drops=20×(4/3)πr³
=20×4×9×9×9×22÷(7×3)
=80×729×22÷21
=61097.14286mm³
=61.09714286cm³
πr²h=61·9714286cm³
⇒h=6cm
⇒remaining height=15-(6+6)cm
=3cm
Answered by
1
I get the answer as 5.7
Similar questions