A copper cube weighs 0.25 N in air, 0.17N when completely immersed in paraffin oil and 0.15 N when completely immersed in water.The ratio of upthrust in oil to upthrust in water is
- 3 : 5
-
4 : 5
- 7 : 10
- 13 : 10
The correct answer is: B
Explanation
Wt. in air = 0.25 NWt.in water = 0.15 N
therefore lost in wt. in water = Upthrust in water
= 0.25 - 0.15
= 0.10 N.
Wt. in paraffin oil = 0.17 N.
.. loss in wt.in oil = upthrust in the oil
Ratio upthrust in oil to upthrust in water
= 0.18/0.10 = 8/10 = 4/5 Or 4 : 5