Properties Of Solids And Liquids Question 262
Question:A log of wood of mass 120 Kg floats in water. The weight that can be put on the raft to make it just sink, should be (density of wood = 600 Kg/m3)[CPMT 2004]
Options:
A)80 Kg
B)50 Kg
C)60 Kg
D)30 Kg
Show Answer
Answer:
Correct Answer: A
Solution:
Volume of log of wood $ V=\frac{mass}{density}=\frac{120}{600} $ =0.2 m3
Let x weight that can be put on the log of wood. So weight of the body = $ (120+x)\times 10\ N $
Weight of displaced liquid= $ V\sigma g=0.2\times 10^{3}\times 10\ N $
The body will just sink in liquid if the weight of the body will be equal to the weight of displaced liquid.
$ (120+x)\times 10=0.2\times 10^{3}\times 10 $
$ \Rightarrow \ 120+x=200 $ \ x = 80 kg
