Question

The object of weight 50N and volume 0.002m^3 is immersed 3/4" of it in
the liquid. The apparent weight of object is found to be (density of water
1 kg/m^3)
a. 25N b. 35N c. 45N
d. 55N​

Answer 1

Answer ⇒ Option (c). 35 N.

Explanation ⇒

Upthrust = Volume of water displaced × density of water × g.

Weight of water displaced = Weight of body inside of the water.

= 3/4 × 0.002

= 3 × 0.001/2

= 15 × 0.0001

= 0.0015 m³.

∴ Upthrust = 0.0015 × 1000 × 10

∴ Upthrust = 15 N.

Now, Weight of body in Air = 50 N.

Apparent weight in water = Weight of body in Air - Upthrust.

∴ Apparent weight = 50 - 15

∴ Apparent weight = 35 N.

Hence, Option (b). is correct.

Hope it helps.