Question

a piece of iron has volume 40 cm³ and has a mass of 300 g find the density of iron in CGS system​

Answer 1

Answer:

Answer

Correct option is

C

6.8 N

Given that,

Volume of body V=10−4m3

Density of iron, ρi=7800kgm−3

Density of water ρw=1000kgm−3

Weight in air,Wa=ρiVg=7800×10−4×10=7.8N

We know that,

Weight in water = weight in air – buoyancy force

Ww=Wa−ρwVg

Ww=7.8−1000×10−4×10

Ww=6.8N

Hence, the weight of body in water is 6.8 N

Answer 2

Answer:

Given that,

Volume of body V=10

−4

m

3

Density of iron, ρ

i

=7800kgm

−3

Density of water ρ

w

=1000kgm

−3

Weight in air,W

a

=ρ

i

Vg=7800×10

−4

×10=7.8N

We know that,

Weight in water = weight in air – buoyancy force

W

w

=W

a

−ρ

w

Vg

W

w

=7.8−1000×10

−4

×10

W

w

=6.8N

Hence, the weight of body in water is 6.8 N