A piece of iron weighs 250N in air and 200N in a liquid of density 1000 kgm‾³. The volume of the iron is?

A. 5.0 x 10^-2 m^-2.
B. 4.5 x 10^-2 m^-3.
C. 2.5 x 10^-2 m⁸.
D. 2.0 x 10^-2 m^-3.

Correct Answer:

Option C = 2.5 x 10^-2 m⁸.

Explanation

With in the air = 250N
wt. in the liquid = 200N
loss in wt. in the liquid = 250 – 200 = 50N
∴ Wt. the liquid of equal vol. of the iron = 50N
∴If the density of the liquid is 1000 lgm^-3
then the volume of the liquid = (N)/D = V = (25kg)/1000 =0.025m³ = 2.5 x 10^-2 m⁸.