Question

A sphere of wax of relative density $0.9$ and volume $18c{m}^3$ has some iron nails pierced into it. It floats on water just completely immersed. The mass of iron nails into it is:

• A. $0.9g$
• B. $1.8g$
• C. $2.7g$
• D. $3.6g$

Answer 1

Answer: (B)

$1.8g$

$\text{Total mass of sphere}=\text{water displaced.}$

$(m+0.9\times 18)=1\times 18$

$m+16.2=18$

$m=1.8g$

$\text{Answer:-(B)}$