Question

Numericals
1. A solid floats with 1/5th of its volume above water. Find the density of solid.

2. The mass of empty plastic bottle is 40gram and it's mass when it is filled with water is weighed when it is filled with oil. Find (i) mass of water, (ii) relative density of oil.

3. A normal force of 50N can produce a pressure of 50000pa. Calculate the area in the force shall act to exert the pressure.

PLEASE ANSWER FAST ​

Answer 1

1.) Let V be the volume and d be the density of the solid then weight of the body =Vdg.
Volume of solid body inside water =V−
4
V
​
=
4
3V
​

Weight of water displaced by immersed portion of the body
=
4
3V
​
×10
3
×g
∴ By the principle of floatation,
Vdg=
4
3V
​
×10
3
g
⇒d=
4
3
​
×10
3
=750kgm
−3
.