Question

what is the upthrust on 90cm^3 of iron when totally immersed in water ​

Answer 1

Answer:

Hi,

Volume of the iron is, V = 90 cm3

Acceleration due to gravity, g = 980 cms-2

(a)

Density of water is = 1 gcm-3

When completely immersed in water the volume of water displaced is equal to the volume of the iron. The up thrust is equal to the weight of the water displaced.

Therefore, up-thrust = V × density of water × g

= 90 × 1 × 980

= 88200 Dyne

(b)

When half immersed in an oil of density 0.7 gcm-3, the volume of water displaced is equal to

Therefore, the up-thrust is = (V/2) × density of oil × g

= (90/2) × 0.7 × 980

= 30870

Answer 2

Answer:

(a).

density of water(d) = 1g/cm³

g= 9.8m/s² =980cm/s²

volume of iron (V)=90cm³

Upthrust= V d g

= 90cm³ × 1g/cm³ × 980cm/s²

= 88200 dyne (0.882 N)

(b).

density of oil(d) = 0.7g/cm³

g= 9.8m/s² =980cm/s²

volume of iron when half immersed(V)

=90cm³/2

=45cm³

Upthrust= V d g

= 45cm³ × 0.7g/cm³ × 980cm/s²

= 30870 dyne (0.3087 N)

HOPE IT WOULD HELP........