A metal cube of edge 5 cm and density `9.0cm^(-3)` is suspended by a thread so as to be completely immersed in a liquid of density `1.2gcm^(-3)`. Find the tension in thread. (Take `g=10ms^(-2)`)

Explanation

Edge of the cube = 5 cm
Volme of the cube = `5^3 = 125 "cm"^3`
Density =`9 "g cm"^(-3)`
So, Mass = Volume x density = 125 x 9 = 1125 g
Weight of the cube = 1125 x 10 = 1125 gf (downward)
Density of liquid = `1.2 "g cm"^(-3)`
Upthrust = Volume x density of the liquid
Upthrust = 125 X 1.2
`therefore` Upthrust = 150 gf (Upward)
Tension in thread = 1125 - 150 = 975 gf