Relative Density

$\mathrm{Relative} \mathrm{density} \mathrm{of} \mathrm{an} \mathrm{object}=\frac{\mathrm{Density} \mathrm{of} \mathrm{the} \mathrm{object}}{\mathrm{Density} \mathrm{of} \mathrm{water}}$

An object floats on water. What should be the relative density of the object?

The ratio of densities of two substances $a$ and $b$ is $3:1$ and the relative density of object $b$ is $4$. The density of substance $a$ is

A jewellery sells gold claiming it has the relative density of $19.3$. A customer after buying an ornament decided to test this. The ornament weighs $34.613 \mathrm{g} \mathrm{f}$ when completely immersed in water and $37.875 \mathrm{g} \mathrm{f}$ in air. Check if the claim made by shop is true or not.

What is the relative density with water of an object which weighs $60 \mathrm{N}$ in air and $30 \mathrm{N}$ in water? Take $g=10 {\mathrm{ms}}^{-2}$.

Explain the making of lactometer.

We need calcium to make a lactometer.

A lactometer can be made from a ballpoint pen refill and a boiling tube.

Select the materials used for making a lactometer from the given below.

You have a ball point refill and a boiling tube, and you want to measure the purity of milk. Which of the following instrument will you make?

Name the instrument used for checking the purity of milk. Explain its making.

How can you make a lactometer?

Which of the following is the SI unit of relative density?

Hydrometer is an instrument used for direct determination of relative density of a liquid.

Name an instrument used for direct determination of relative density of a liquid.

The principle upon which a lactometer works is

The instrument used to measure the purity of milk is

Which of the following instruments is used to check the quality of the milk?

A lactometer is used to check the quality of milk by checking the:

The _____ density has no units.

The relative density of an object is defined as the ratio of its density to the density of water at _____ °C.