Question

Metallic block of density 5 g cc having dimension 5x5x5 weighed in water apparent weight would bee

Answer 1

As the question didn’t mentioned the unit of volume I’m taking it in centimetres.

Density = 5 g/cm³
Volume = (5 cm)³ = 125 cm³
Relative Density (σ) = (5 g/cm³) / (1 g/cm³) = 5

Weight in air = mg
= Volume × Density × g
= 125 cm³ × 5 g/cm³ × 9.8 m/s²
= 6125 g m/s²
= 6.125 kg m/s²
= 6.125 N

Apparent weight = Weight in air [1 - 1/σ]
= 6.125 N × [1 - 1/5]
= 4.9 N

Apparent weight of block is 4.9 N

Answer 2

Density = 5 g/cm³

Volume = (5 cm)³ = 125 cm³

Relative Density (σ) = (5 g/cm³) / (1 g/cm³) = 5

Weight in air = mg

= Volume × Density × g

= 125 cm³ × 5 g/cm³ × 9.8 m/s²

= 6125 g m/s²

= 6.125 kg m/s²

= 6.125 N

Apparent weight = Weight in air [1 - 1/σ]

= 6.125 N × [1 - 1/5]

= 4.9 N

Apparent weight of block is 4.9 N

OR

4*5*5*5 for relative density