Question

What do you mean by the those sentences which are bracketed here?

13. A body thrown vertically upward will have zero velocity at the highest point in its motion, but it have downward acceleration equal to 9.8 m/s² due to gravity.
The correct answer is C.

14. Density of a solid body is defined as:

$Density=\frac{Massofbody}{Volume}$
Since a body, when immersed in water, displaces volume of water equal to its own volume, desity can also be expressed as :

$\mathrm{relative}\mathrm{density}=\frac{\mathrm{Density}\mathrm{of}\mathrm{the}\mathrm{solid}\mathrm{body}}{\mathrm{Density}\mathrm{of}\mathrm{water}}=\frac{\mathrm{Weight}\mathrm{of}\mathrm{the}\mathrm{solid}\mathrm{body}\mathrm{in}\mathrm{air}}{\mathrm{Weight}\mathrm{of}\mathrm{the}\mathrm{displaced}\mathrm{water}}$
Weight of the displaced water = Loss of weight of the solid body in the water It is given that the weight of the sample solid in air is 12 kg f and the same in water is 8 kg f. Therefore.

$Relativedensityofthesolid=\frac{Weightofthesolidbodyinair}{Lossofweightofthebodyinwater}$

$$\begin{gathered} =\frac{12}{12-8} \\ =\frac{12}{4} \\ =3 \end{gathered}$$

Relative density of a liquid can be defined as:

Answer 1

Dear Student

The sentence in the bracket is the weight of the displaced water is equal to the loss of the weight of the solid body in water.

This can be well explained by archimedes principle which states that the upward force or the buoyant force which is acting upwards on the immersed body in fluid is equal to the weight of the fluid displaced by the body.

The upward force or the buoyant force is equal to the loss of the weight of the solid body immersed in the liquid. So, the statement clarifies that weight of the displaced water is equal to the upward force or the loss of the weight of solid body in water.

Regards