Force required to immerse a wooden cube

[Jahnavi]

Homework Statement

The force required to immerse a wooden
cube of side 4 cm and relative density RD 0.5 completely in water is
1) 16x10^-3 kgwt
2) 32x10^-3 kgwt
3) 64x10^-3 kgwt
4) 128x10^-3 kgwt

Homework Equations

The Attempt at a Solution

Density of the cube = 0.5 gcm^-3
Volume of cube = 64 cm³
Weight of the cube = 64 x10^-6 x 500 x 9.8 N (1)

Upthrust = 64 x10^-6 x 1000 x 9.8 N (2)

Force required = Upthrust - Weight

Subtracting (1) from (2)

Force required = 64 x10^-6 x 500 x 9.8 N

1kgwt = 9.8 N

Force required = 32 x10^-3 kgwt

Is option 2) the correct answer ?

 

[scottdave]

it looks good to me.